The Sri Lankan government has rejected a report commissioned by the UN on alleged human rights violations at the end of the country's war two years ago.
The report, by a panel of rights experts, has just been submitted to UN Secretary-General Ban Ki-Moon and to the government in Colombo.
Human rights groups are demanding that the report be made public.
The government has been fundamentally opposed to the panel of experts since its appointment by Mr Ban last year.
It declined to admit them to the country to conduct research.
The three-member panel, headed by a former Indonesian attorney-general, was mandated to look into issues of accountability connected with the war.
UN officials say this refers to allegations that war crimes may have been committed by either the government or Tamil Tiger separatists, whose top leaders are now dead.
The UN says it is "unacceptable" that large numbers of civilians were killed - numbers it estimates to be in the thousands.
The Sri Lankan government has now seen the panel's report and has swiftly rejected it.
A foreign ministry statement described it as "fundamentally flawed in many respects", and as being based on "patently biased" and unverified material.
Mr Ban is studying the report and his spokesman says it will be made public at some point.
The government maintains that the military inflicted no civilian deaths during the final stages of its victory.
International human rights groups, however, say that thousands of civilians were killed, that both sides were responsible and that a war crimes inquiry is needed.