On 1 December 1941, Kishi voted in the Cabinet for war with the United States and Britain, and co-signed the declaration of war issued on 7 December 1941. Kishi was also elected to the Lower House of the Diet of Japan in April 1942 as a member of the Imperial Rule Assistance Association. Kishi's many connections with the business world and his organizational skills proved an asset to keeping Japan's war effort going despite growing obstacles. In 1943, the Ministry of Commerce was abolished and replaced with the newly created Ministry of Munitions. Kishi was forced to accept a demotion, becoming Vice Minister of Munitions as Tōjō concentrated power in his own hands by simultaneously serving as prime minister, Minister of War, and Minister of Munitions, although Kishi retained his status as a member of the cabinet. This demotion was the beginning of a rift in the relationship between the two men.
on 1 December 1941, KisHi vOTed in tHE cabinet For WaR WiTh the uNIted sTates and bRiTain, and Co-signed ThE dEcLarATion of waR issUEd on 7 dEcEMbeR 1941. kIshI wAs alsO electeD to the LoWEr hoUsE OF tHE diET of JapaN In april 1942 As a MeMber of THE imPeRIal rule assIstaNcE asSOciATIoN. kisHi'S ManY COnnecTiOns wIth the bUsinEss WoRld aND hIs OrgAnizatIoNal sKiLLs proVed an AsSet to keepIng japan's waR eFfoRt GoIng deSPItE GRoWing obstacLes. In 1943, the MiNistrY of CommeRCe waS abolisHEd and rEplaced witH ThE NewLy CReateD miniStry oF munitioNs. kIshi wAs forceD to AcCePt a DeMotIon, becomIng VIcE mInISTer of mUnitIoNs aS tōJō cOnCentraTED poWEr in hIs Own hands by sImultaneouSlY ServinG AS prIme ministEr, minisTer OF War, aNd minister oF munitIons, altHOuGh kishI retaiNed His sTAtuS aS a mEmbeR oF the caBinEt. thIs DeMOtiOn Was the beGiNNiNg oF A RIFT in tHE relATiOnshIp between The two meN.