United Nation (UN) Secretary-General Ban Ki-moon visited a displacement camp packed with Tamil civilians and flew over the former battlefield Saturday as he appealed to Sri Lanka's triumphant government to "heal the wounds" after three decades of civil war.

The secretary-general was the first major international figure to visit since President Mahinda Rajapaksa declared victory over the Tamil Tiger rebels on Monday, crushing their dream of a separate state for the Tamil minority.

Nearly 300,000 Tamil civilians were displaced in the final months of fighting and sent to dozens of government-run camps in the north.

Ban toured a section of the massive Manik Farm camp, went into people's tents to see their living conditions, spoke to displaced people and met with the wounded in a hospital.

Unfettered access

"The situation, which I have seen for myself, is very, very difficult. It's a real challenge," Ban said. "There is clearly a limitation. The United Nations should try to fill this gap."

Ban called on the government to give aid groups unfettered access to the camps and welcomed Rajapaksa's promise to resettle the bulk of the displaced by the end of the year.

"We will try to work hard to make sure that promise is realised," he said, as he toured the vast expanse of white tents neatly lined up in rows on dirt paths.

Roads between the tents were crammed with people, and barbed wire fences encircled the area, keeping the tens of thousands of civilians from getting out. Soldiers were stationed across the camp.

Men and women were scooping water from a well and bathing awkwardly in the open air, trying to maintain some privacy.

Aid groups have appealed to the government to allow the displaced more freedom, but military officials say it is too dangerous to let them out because rebels could be hiding among the civilians.

Mark Cutts, a senior UN humanitarian officer, said the Manik Farm camp was erected almost overnight and is the world's largest displacement camp.

"There's 200,000 people here. This is a very overcrowded place, a very big place, and there's a lot of work still to be done. Conditions, you can see, they're very basic," he said.

Human rights groups

Ban later flew by helicopter over the wasteland along the northeastern coast where the final battles raged. The earth was scorched and the area was pocked with craters. Cars and trucks were overturned and bunkers were dug outside tents clustered in the area.

Human rights groups and international officials accused the government of heavily shelling the area, densely populated with civilians, in the last weeks of the war. The government denied using heavy weapons.

The UN chief then flew to the central city of Kandy to meet with Rajapaksa.

Before that meeting, the nation's top Buddhist monks presented Rajapaksa with the country's highest honour at a temple reputed to house Buddha's tooth.

Rajapaksa pledged to ensure that the nation will never be divided again.

"We shall from now meet all such needs to build a just and free society," he said.

The Tamils, 18 per cent of the population, claim systematic discrimination and harassment by the Sinhalese majority."