( CNN ) -- Sri Lanka 's prime minister warned Saturday that his country `` stands on the brink , '' as its soldiers cornered Tamil Tiger fighters in an assault that is trapping more than 50,000 civilians on a small plot of coastal land . Sri Lanka 's defense ministry says this handout photo shows troops with a captured Tamil Tiger craft Thursday . The United Nations estimated the number of civilians , who were trapped on about 1.5 square miles ( four square kilometers ) of land . Government troops seized the last remaining coastal stretch under the control of Tamil Tiger rebels , the Ministry of Defense said Saturday , marking a possible end to more than 25 years of fighting in the island nation . The seizure marks the total capture of coastline territory previously controlled by the rebels , it said , after army divisions advanced from the north and south to link up . An army source told CNN that about two square kilometers in the region remain to be captured , and that military officials expect that to happen in a couple of days . The rebels -- formally known as the Liberation Tigers of Tamil Eelam ( LTTE ) -- have fought for an independent state for minority Tamils in Sri Lanka since 1983 . As many as 70,000 people have been killed since the civil war began . `` Sri Lanka stands on the brink , '' Prime Minister Rathnasiri Wickremanayake said in a written statement . Watch aid agencies fear for Sri Lanka » . `` We have called repeatedly for the violence to cease . The humanitarian agencies must be granted access to civilians caught in the crossfire of a dreadful conflict . Watch iReporter Thileepan 's footage of the `` safe zone '' » . `` We are backing U.N. efforts to secure an orderly end to the conflict . The LTTE must lay down its arms and allow civilians to leave . Sri Lanka must understand that there will be consequences for its actions . '' No formal declaration of victory is expected at least until Sri Lankan President Mahinda Rajapaksa returns to the country from Amman , Jordan , where he is attending the World Economic Forum . In an address to the summit in Amman on Saturday , Rajapaksa said the Sri Lankan armed forces had defeated the rebels . `` I will be going back to my country Sri Lanka that has been totally freed from the barbaric acts of terrorism of the LTTE . This freedom comes after 30 long years . '' `` Our economic prosperity must essentially rest upon global peace and stability . Terrorism has for decades denied us this right . All eleven countries gathered here today have suffered the effects of terrorism , some more than others . `` Terrorism has raised its ugly head in different forms from time to time and destroyed all development initiatives in most of our countries '' he said . On Friday , the Navy arrested the wife of Soosai , a leader of Sea Tigers -- the ocean-going arm of the rebel group . His daughter and son-in-law were also arrested . Navy officials , quoting those who were arrested , said Tigers leader Velupillai Prabhakaran is believed to be inside the area of the latest fighting . Other sources have said he has escaped . CNN 's Iqbal Athas contributed to this report .
No formal declaration of victory expected until President Mahinda Rajapaksa returns . PM : Country is on the brink , we have called for violence to stop . We are not going to allow this situation to continue any longer. Navy officials : Tigers leader Velupillai Prabhakaran believed to be in area of fighting .