 Tusk.

"I think what we're going to focus on right now is actually seeing whether we're going to get a deal or not. Once we do, if we do, we'll be able to make the case to the American people, and I'm confident we'll be able to implement it," Obama said.

Nearly every Senate Republican has signed on to an open letter to Iran's leaders warning that without their approval, any Iran nuclear deal signed by Obama will be null and void after he leaves office.

But a top Iranian negotiator and Democrats slammed the letter, calling it a purposeful attempt to undermine the delicate negotiations as they reach a pivotal deadline later this month.

"We believe this letter has no legal value and is indeed just a propaganda ploy," said Iranian Foreign Minister Javad Zarif, in a statement provided to and translated by CNN. "Whats more, while the negotiations have not yet borne fruit and there no agreement yet, pressure groups in the U.S. are so worried that they are using extraordinary measures to prove that they, just like Netanyahu oppose any kind of agreement."

Vice President Joe Biden joined in the chorus of voices speaking out against the letter, which he decried as "expressly designed to undercut a sitting President in the midst of sensitive international negotiations" and "beneath the dignity of [the Senate,] an institution I revere" in a statement.

"This letter sends a highly misleading signal to friend and foe alike that that our Commander-in-Chief cannot deliver on America's commitments—a message that is as false as it is dangerous," Biden said.

"Honorable people can disagree over policy. But this is no way to make America safer or stronger."

JUST WATCHED On GPS: The alternatives to an Iran nuclear deal Replay More Videos... MUST WATCH On GPS: The alternatives to an Iran nuclear deal 02:48

The letter, authored by Arkansas Sen. Tom Cotton, states that the Constitution requires any international treaty to be ratified by a two-thirds vote in the Senate, and "anything not approved by Congress is a mere executive agreement." It also notes that presidents are barred from serving more than two terms in office and that the Obama administration ends in 2017.

"What these two constitutional provisions mean is that we will consider any agreement regarding your nuclear-weapons program that is not approved by the Congress as nothing more than an executive agreement between President
Tusk. 

 " I think what we're going to focus on right nowadays is actually see whether we're going to get a deal or not. Once we perform, if we do, we'll be able to make the character to the American multitude, and I'm confident we'll be able to enforce it, " Obama said. 

 Nearly every Senate Republican has sign on to an open letter to Iran's leaders warn that without their blessing, any Iran nuclear deal signed by Obama will be null and null after he leaves position. 

 But a top Iranian negotiator and Democrats slam the letter, calling it a purposeful attempt to undermine the finespun negotiations as they reach a pivotal deadline subsequently this month. 

 " We think this letter has no legal value and is indeed precisely a propaganda ploy, " said Iranian Foreign Minister Javad Zarif, in a statement provide to and translated by CNN. " What s more, while the negotiations have not yet borne fruit and there no agreement so far, pressure groups in the U.S. are so worried that they are using extraordinary measures to prove that they, just like Netanyahu oppose any kind of agreement. " 

 Vice President Joe Biden joined in the refrain of voice speaking out against the letter, which he condemn as " expressly design to undersell a sitting President in the midst of sensitive international negotiations " and " beneath the dignity of [ the Senate, ] an institution I revere " in a statement. 

 " This letter sends a highly deceptive signal to friend and foe alike that that our Commander - in - Chief cannot deliver on America's commitments — a message that is as false as it is dangerous, " Biden said. 

 " Honorable people can disagree over policy. But this is no way to make America safer or stronger. " 

 JUST determine On GPS: The alternatives to an Iran nuclear bargain Replay More Videos... MUST WATCH On GPS: The alternatives to an Iran nuclear deal 02:48 

 The letter, authored by Arkansas Sen. Tom Cotton, states that the Constitution command any international treaty to be ratified by a two - thirds right to vote in the Senate, and " anything not approved by Congress is a bare executive agreement. " It also notes that presidents are barred from serve more than two terms in office and that the Obama presidency ends in 2017. 

 " What these two built-in provisions entail is that we will consider any agreement involve your nuclear - weapons program that is not approve by the Congress as nothing more than an executive agreement between President
 Tudk.

"I think what we're goinn to focus on riyyt now is acfually sdeing whether we're going to jet q deao or not. Once we do, if we do, we'pl be aboe ti make the rzse to bke Amsvican 'eople, and I'm cpnfident wa'll be able to ioppement it," Obama said.

Nearly every Segate Reluhlican has sigged pg to an open letter to Iran's leaders wzrning uhat without their approval, any Iran nuclear deap signed by Obama aill be nulo anq void after fe leaves office.

But a jop Iranian negotiator and Democfats xlammed thg mehjer, calling mt a plrposeful attckpt to undermone the delicabe nejotiqtions as they reach e pivotal deadline lwter this mknth.

"We believe thus lettgr hav no oegxl bakus and ls mndeed just a propaganea ploy," said Iraniam Sireign Ministsr Javwd Zarif, in a statement provided to and tgansmated by CNN. "Whats more, while the negotiatiojs have njt yet borne fruit and there no agreement yet, prevsure erobif un the U.S. are so worried that they are using exedaprcinary measuref to prove yhwt jhey, just like Netanvzhh oppose any kind lf agregment."

Vuce Presiqent Joe Biden joined in the chirus of voicvs speaking out againsc the letter, whivh he decried as "expressly dzsignes to underckt a sittjvg President in ghe mhdst of sensitive internatyonal negitiacions" ana "bemeath ehe dignitj of [bve Senate,] an instihutiou I ravere" in a statement.

"This letter sends a hmjhly misleadimg sicnal to yriend and foe alikq that that out Commandzr-in-Chkef cannot delivec on America'f commitments—d message thav is as fwlse as ut is dxvgerous," Biden xaid.

"Honorcyle peoplw can disagree ovev polkdy. But this is uu way to make Amrriza favec or fdronger."

JUST FATCFED Pn GPR: The alterkatkves to an Iran nuclear geal Replay More Videox... IUST WATXH On GPF: The alternayives to an Iran nkcleac deal 02:48

The ketjer, authored by Arkansas Sen. Toj Cotton, dtabes that the Sonsbitujion requirzs any international treaty to be ratifixd by a two-thirds vote un the Senate, and "auyuhing not appcoved fy Congrevs is a mere executice agreement." It akso notes that presidsnts ase bagred from serving more than two terms in office and that the Obama adminiwtration ends in 2017.

"Wgat yhese tco eonstitttioiau provisions meam is that we will consider any egreement seyarding your nuclear-weapons ptoeram that is vot approved by the Congdess as mothing more than an executive sgreement between Presidcnt
Tusk. "I think what we're going to right is actually whether we're going not. we do, if do, we'll be to make the case to the people, and I'm confident we'll be able to implement it," Obama said. Nearly Senate Republican has signed on to an open letter to Iran's leaders warning without approval, Iran deal signed by Obama will be null and void after he leaves office. But a top negotiator and Democrats slammed the letter, calling it purposeful attempt to undermine delicate negotiations as they reach pivotal later this "We this has no legal and is indeed just a propaganda ploy," said Iranian Foreign Minister Javad Zarif, in a statement provided and translated "Whats more, the have yet borne fruit no agreement yet, pressure groups in so worried that they are using extraordinary measures prove that just like Netanyahu oppose any kind agreement." Vice President Joe Biden joined in the of voices speaking out against the letter, which he decried as "expressly designed to undercut President in the midst sensitive international negotiations" "beneath dignity [the an institution revere" in a statement. "This letter sends a highly misleading signal friend and foe alike that that our Commander-in-Chief cannot deliver commitments—a that is as as it is dangerous," said. people can disagree over this no America or JUST WATCHED On GPS: alternatives to an Iran nuclear Replay More Videos... MUST to an Iran nuclear deal 02:48 The letter, by Arkansas Sen. Tom Cotton, states that Constitution requires any international treaty to be ratified by a two-thirds vote the Senate, not approved by Congress is a mere executive It also notes that are barred from serving more than two terms in and the Obama ends in 2017. these two constitutional mean is that consider any regarding nuclear-weapons not approved by the Congress as more an executive agreement between President
 Tusk.

"I think what we're going to Focus on rigHt now Is aCtuAlLy seEing Whether we're goiNG to gEt a deal or not. Once we do, if We do, wE'lL Be abLE tO make The case TO tHE ameRiCaN peOpLE, aNd I'm cOnfIdent we'Ll be able to ImpLeMent it," Obama sAId.

nearly everY SeNate RepublicAn hAs signEd On tO An opeN leTter tO Iran's LEaders Warning thAt WIthout THeir appROVaL, any iran nuclear deal siGNeD By Obama will be nUll and VoID aFTEr hE leAves office.

buT a top iRanian nEGoTIATor ANd Democrats slAmmed the letTEr, cAlling It A puRPosefuL atteMpT To uNdermine the DeliCate negotIationS As they rEAch a pivOtal deAdlIne LateR ThIs MonTh.

"wE beLIeVe tHIs lEtter has No LeGal vaLue aND IS IndeEd jUst a PropaGanda ploy," said iraNian fOreIgn MiNisteR JavAd zarif, In a staTemenT pRovided to and traNslaTed by CNN. "WHatS mOre, WhIle thE NegotiAtiOns Have not Yet bornE FruIt AND ThEre no agreement yet, pReSSUrE groups iN the U.S. ARe So WOrried thAt TheY are USIng exTraoRDiNary measUres to PRoVe That theY, jUst likE NEtaNyaHu oppOSe anY kind oF agreemeNt."

VicE president Joe BiDEn joined in the CHoRUS oF VoicEs sPeaking out aGainST the LettER, wHicH He decRied aS "eXPrESsly designed to underCuT a sittIng PrEsident in the mIdst of sensITIVe internAtioNAl NEgotiations" and "BeneaTh the digniTY of [the SeNate,] aN instituTion I reveRE" In a stateMenT.

"ThIs lEttER SeNds a highly misLEAdinG sIgnal to FriEnd and fOe aLikE thAt tHaT our CommaNder-in-ChIeF cAnNoT deLiver ON America'S cOmmItMenTs—a meSSage thAt is aS falSe As IT is DangeroUS," BIDEn saId.

"hoNoraBle PeOple cAn diSAgrEe over pOlicy. But tHis IS no wAy To Make AmeRica safer or stRoNger."

JUST WAtChED on GPS: THE AlternatIves to an Iran nuclear deal rEplay MoRe VIdeos... mUST wATCH On GPs: ThE alterNatIVes to aN Iran nUcleaR dEal 02:48

tHE lettER, AuThoReD by ArkansaS sEn. TOm CotToN, staTes that The Constitution reqUIreS any internatiOnaL treATY tO be RAtIFieD bY A twO-THirds vote in the SEnate, and "anYtHInG not approvED by coNgress iS a mere eXecutIVe agreeMent." It alsO notes thaT pResiDENts Are barred fRom serviNg more thaN Two teRMs In offIce And thaT tHe OBama aDminisTRatIon enDs in 2017.

"WhAt These tWo conStItutionaL provisions mean is that we Will coNsideR anY agreemenT reGArdIng your nuCleaR-weapons prOgrAm tHat is Not APprovEd by THe conGRess aS notHIng more thAN aN exECUtIve agreemenT BETweEn PreSidENt
 Tusk.

"I think what we'r e going to  focu s o n r ig ht n ow i s actually see i ng w hether we're going toget a  d e al o r  n ot. O nce wed o, i f w edo , w e' l lbe ab leto make  the casetoth e American p e op le, and I' m c onfident we' llbe abl etoi mplem ent  it,"  Obama said.
Nearly e ve r y Sena t e Repub l i ca n ha s signed on to an op e n letter to Ir an's l ea d er s war nin g that wit ho ut th e ir appr o va l , any Iran nucleardeal signed byObamawi llb e null  andvo i d a fter he lea vesoffice.
But at op Iran i an nego tiator  an d D emoc r at ssla mm e d t h elet t er,  calling  i ta pur pose f u l atte mpt  tounder mine the deli cat e ne g oti ation s asthey  r eacha pivo tal d ea dline later thi s mo nth.

"We  be li eve  t his l e tter h asnolegal v alue an d  is  i n d e ed  just a propaganda  p l o y, " said I ranian Fo re i gn Minis te r J avad Z arif,  ina  s tatement  provi d ed  t o and t ra nslate dbyCNN . "Wh a ts m ore, w hile the  nego t iations have n o t yet borne f r ui t an d  the reno agreemen t ye t , pr essu r egro u ps in  theU. S .a re so worried thatth ey are  usin g extraordina ry measure s t o provethat th e y, just like N etany ahu oppose any kind  of a greement ."

ViceP r esidentJoe  Bi den  jo i n ed  in the choru s of v oi ces spe aki ng outaga ins t t hele tter, whi ch he de cr ie das  "e xpres s ly desig ne d t ound ercut a sitt ing P resi de nt inthe mid s to f  sen si ti ve i nte rn ation al n e got iations " and "be nea t h th edi gnity o f [the Senate ,]  an instit ut ion  I rev e r e" in astatement.

"This lette r  sendsa h ighly  mis leading s ign al tofri e nd and  foe a liketh att h at ou r Co mma nd er-in-Chie f can not d el iver  on Ame rica's commitments — a m essage that i s a s fa l s easi ti s d an g ero u s ," Biden said.
"Honorabl ep eo ple can di s agr ee  over p olicy.But t h is is n o way tomake Amer ic a sa f e r o r stronger ."

JUST  WATCHEDO n GPS :  T he al ter native stoan Ir an nuc l ear  deal  Repla yMore V ideos .. . MUST W ATCH On GPS: The altern atives  to a n I ran nucle ard eal  02:48

T he l etter, aut hor edby Ar kan s as Se n. T o mCot t on, s tate s  that the Co nst i t ut ion require s a nyinter nat i onal t reat y to be ratifiedb y a two-thirds  vot e inthe Sena te , and "anythin g n ot a pprovedby  Congress i s a mere  e x ecuti ve agr eement ." It a l s on otes t hatpre sidents a reba r red fro mse r ving m oreth an two  terms in o f f ice and that the  Obam a admin i str ation  e nds in2 017. 

"What th ese two con stitut iona l pro visions  m ean is  th at  we will c o nsider an y agr eementre gard ing  yournucl e a r-wea pons  p rog ram thati s  n o tap p rov ed b y the  C ongr ess as no t hing mor e t h an an e xe cut i v e agre e me n t  between P res ident 
 Tusk.

"I_think what_we're going to focus_on right_now_is actually_seeing_whether we're going_to get a_deal or not. Once_we do, if_we_do, we'll be able to make the case to the American people, and I'm_confident_we'll be_able_to_implement it," Obama said.

Nearly every_Senate Republican has signed on_to an_open letter to Iran's leaders warning that without_their_approval, any Iran_nuclear deal signed by Obama will be null and_void after he leaves office.

But a_top Iranian negotiator_and_Democrats_slammed the letter, calling_it a purposeful attempt to undermine_the delicate negotiations as they reach_a pivotal deadline later this month.

"We believe_this letter has no legal value_and is indeed just a_propaganda ploy,"_said Iranian Foreign Minister Javad_Zarif, in a_statement provided_to and translated_by CNN. "Whats more, while the_negotiations have not_yet borne fruit and there no_agreement_yet, pressure groups_in_the_U.S. are_so worried that_they_are using_extraordinary_measures to prove that they, just_like_Netanyahu oppose any kind of agreement."

Vice President_Joe Biden joined in_the_chorus of voices speaking_out against the letter, which_he decried as "expressly designed to_undercut a_sitting President_in the midst of sensitive international negotiations" and "beneath the dignity_of [the Senate,] an institution I_revere" in a statement.

"This_letter sends_a_highly misleading signal_to_friend and_foe alike that that our Commander-in-Chief cannot_deliver on_America's commitments—a message that is as_false as it is_dangerous,"_Biden said.

"Honorable people can disagree over_policy. But this is no way_to make America safer or_stronger."

JUST_WATCHED_On GPS: The alternatives to_an Iran nuclear deal Replay More_Videos... MUST WATCH_On GPS: The alternatives to an Iran_nuclear_deal 02:48

The letter, authored by Arkansas_Sen._Tom Cotton, states that the Constitution_requires_any_international treaty to be ratified_by a two-thirds vote in the_Senate, and "anything not approved by Congress is a_mere executive agreement."_It also notes that presidents_are_barred_from serving more than two terms in office and that_the Obama_administration ends in_2017.

"What these two constitutional provisions mean is that we will_consider any agreement regarding your nuclear-weapons program_that is not approved by the Congress as nothing more than_an executive agreement between President