An unmarked mass grave has been found in Sri Lanka's former war zone, the first discovery of an unmarked gravesite since troops defeated Tamil rebels more than four years ago, police said Sunday.

Construction workers in the coastal district of Mannar stumbled on at least 10 skeletal remains buried at a location where they were laying a new water pipe, said police spokesman Ajith Rohana.

Sri Lanka is considering a South African-style reconciliation commission nearly five years after crushing Tamil separatists in an offensive that triggered international allegations of war crimes, a minister said Tuesday.

Information minister Keheliya Rambukwella said President Mahinda Rajapakse, who attended a memorial service for former South African president Nelson Mandela in Johannesburg last week, was trying to replicate the late civil rights icon's reconciliation bid.

The Catholic church Wednesday warned Sri Lanka's government of foreign intervention unless it worked towards reconciliation and addressed allegations of war crimes during the war against Tamil separatists.

Malcolm Ranjith, the archbishop of Colombo, said he was urging President Mahinda Rajapakse and the main ethnic Tamil party to hammer out a political settlement or risk an international probe.

Sri Lanka is to begin a nationwide survey to determine the number of people who were killed in the country's 37-year ethnic conflict, the government said Wednesday.

"The Department of Census and Statistics will conduct an island-wide census to assess the loss of human life and damage to property," said a government statement posted on President Mahinda Rajapakse's website.

Nelson Mandela remains in a "stable but critical" condition, but "continues to respond to treatment," according to the South African government, issuing its first update on his health since September.

"The health of the former President remains much the same," according to a statement issued after President Jacob Zuma visited the anti-apartheid icon at his home Monday.

Commonwealth leaders signed agreements Sunday on issues such as poverty and development as they staged a show of unity after a summit in Sri Lanka dominated by a bitter dispute over war crimes.

After a three-day meeting in Colombo, Sri Lankan President Mahinda Rajapakse announced a declaration had been signed by the Commonwealth's 53 member nations after a summit which he said had been characterized by "fruitful discussions.”

Australia said Sunday it would give Sri Lanka two patrol boats to tackle people-smuggling in the Indian Ocean, but the government came under fire for collaborating with Colombo.

Canberra is hoping that boats can be detected before they leave the island's waters as the Australian government intensifies efforts to deter asylum-seekers arriving by boat, a sensitive political issue.

Britain's David Cameron put Sri Lanka on notice Saturday to address allegations of war crimes within months or else he would lead a push for action at the U.N.

Speaking at a troubled Commonwealth summit in Colombo, the British premier warned his hosts that pressure over alleged abuses at the end of Sri Lanka's ethnic conflict was not about to go away.

Sri Lankan President Mahinda Rajapakse told Britain's Prime Minister David Cameron Friday his country needed more time to address concerns about the plight of minority Tamils after the end of its ethnic conflict.

"As it is now only four years since the end of the conflict, the country needs some more time to overcome all major challenges", Rajapakse said, according to a statement from his office, after talks with Cameron in Colombo.

Sri Lanka's president urged his peers Friday not to pass judgment over his country's past as he hosted a Commonwealth summit that threatens to be upstaged by a visit to the war-torn north by Britain's David Cameron.

The summit was meant to be a chance for President Mahinda Rajapakse, a Sinhalese nationalist leader who oversaw the crushing of Tamil Tiger rebels in 2009, to showcase the development of his country.