UN Secretary-General Ban Ki-moon toured Sri Lanka's largest war-displaced persons camp on Saturday to press for wider humanitarian access and political reconciliation.
In the highest-level international visit to Sri Lanka since the country's government declared victory on Monday over the Liberation Tigers of Tamil Eelam (LTTE), the secretary-general was also due to fly over the final battleground of the war against the rebels and then to meet President Mahinda Rajapaksa.
The United Nations wants full access to camps housing 290,000 people who escaped LTTE-controlled areas as a military onslaught reached its climax.
UN aid agencies have complained about a lack of full access to the refugees, whose condition has caused widespread concern, but Sri Lanka says it needs time to weed out potential Tamil Tiger infiltrators hiding in the camps.
Not a defeat for the Tamils - president
Mr Ban said he would encourage open political discussions between the majority Sinhalese and minorities including Tamils when he met Mr Rajapaksa later on Saturday in Kandy, the historic seat of Sinhalese kings and a Buddhist holy site.
Mr Rajapaksa has already pledged to strike a political deal with Tamils, saying he does not want Sri Lankans viewing the victory over the LTTE, which fought to create a separate nation for the Sri Lankan Tamil minority, as a defeat of the Tamils.
He has also pledged to resettle most of the 280,000 Tamils displaced by the war within six months.
The United Nations has estimated that the 25-year war killed between 80,000 and 100,000 people altogether.