He told journalists that the establishment of the panel was in line with a joint statement he had issued with Sri Lankan President Mahinda Rajapaksa during his visit to Sri Lanka last May after Government forces had defeated the LTTE.

"This joint statement contained a commitment related to ensuring an accountability process for addressing violations of international humanitarian and human rights laws," Moon said in response to questions from reporters at his monthly press conference at the UN Headquarters in New York.

"The panel I am establishing will advise me on the standards, benchmarks and parameters, based on international experience, that must guide any accountability process such as the one mentioned in the joint statement. Now this panel will report to me directly and not to another body."

UN General Secretary said a recent letter on the subject he received from the Non-Aligned Movement (NAM) had indicated that there was a misunderstanding on the nature and purpose of the experts panel.

"I am convinced that it is well within my power as Secretary General of the United Nations to ask such a body to furnish me with their advice of this nature. This does not in any way infringe on the sovereignty of Sri Lanka."

Last week the UN chief voiced concern about the lack of progress on political reconciliation, the treatment of internally displaced persons (IDPs) and the setting up of an accountability process since he reached the joint statement with President Rajapaksa.

Earlier this month Ban Ki-moon had what he described as "a frank and honest exchange of views" by telephone with Rajapaksa.