Australian Foreign Affairs Minister Kevin Rudd says new information about atrocities against Sri Lankan civilians at the end of the civil war is appalling.
A new British television documentary has shown evidence of civilians being killed by government troops.
The 26-year war, which ended in 2009, was waged between Tamils seeking to create their own state and the Sri Lankan government and military.
Last year, a United Nations panel of experts found there was credible evidence that up to 40,000 civilians were killed in the war.
Mr Rudd says the UN’s Human Rights Council needs to reinvestigate the issue.
“I believe their deliberation on it was inadequate and I would call upon – as does the Australian Government through its mission in Geneva – the Human Rights Council to revisit this matter and to examine once again whether their original findings can any longer be regarded as well founded,” he said.