President Mahinda Rajapaksa told a news conference that Sri Lanka had nothing to hide and "will take our time and we will investigate into nearly 30 years of war."
He added: "If there are any allegations we are ready to inquire into it. We have nothing to hide. It's a free country. We need time to settle things."
The Prime Minister's historic visit to northern Sri Lanka highlighted human rights issues at the start of the Commonwealth summit.
A press conference due to be held today with Sri Lankan President Mahina Rajapaksa was cancelled at the last minute.
Democratic freedoms are being clipped and police vans are waiting for those who might disagree what the Sri Lankan government is doing.