The Sri Lankan president says he hopes to set up a domestic inquiry into alleged war crimes committed during the country's civil war within a month.
Maithripala Sirisena said UN investigators would not be involved, despite international pressure.
He was speaking to the BBC's Sinhala service while on a visit to London.
The Sri Lankan army defeated the Tamil Tiger separatists in 2009, ending a 26-year long conflict. Both sides have been accused of atrocities.
Mr Sirisena said he expected the investigative committee tasked with examining alleged human rights abuses would work "efficiently, in a balanced, legal and impartial manner".
He told BBC Sinhala's Saroj Pathirana that advice from the UN would be taken into account but there was no need for them to be involved in the inquiry.
The Sri Lankan president meets Queen Elizabeth
The Sri Lankan president met Queen Elizabeth while on his visit to Britain
The UN agreed last month to delay its long-awaited report into alleged war crimes in Sri Lanka, saying the new government was more willing to co-operate than the previous administration.
Mr Sirisena came to power in January, inflicting a surprise defeat on his one-time ally, Mahinda Rajapaksa.
In his interview, he echoed allegations that Mr Rajapaksa tried to mount a coup after his loss but was thwarted by the election commissioner and police chief.
Mr Sirisena received large numbers of votes from Tamils and Muslims in the poll, the country's two largest minorities.
He said he was committed to reconciliation: "We expect to begin a new journey to promote reconciliation, cohabitation, brotherhood and friendship among the people of Sri Lanka, and to win over international opinion on these issues."
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