Sri Lanka's president says it will be a "grave crime" if anyone brings war crime allegations against his government over its conduct in the final months of a quarter-century civil war, adding it would be a victory to forces opposed to peace in the island nation.

Mahinda Rajapaksa did not mention any country in an Independence Day speech Tuesday, but the United States has said that it is frustrated at Sri Lanka's lack of progress in post-war reconciliation and accountability and says it will bring a third resolution to the United Nations human rights body calling on Sri Lanka to do more. Details of the resolution have not been revealed.

Rajapaksa vowed not be frightened by the proposed resolution.

Sri Lanka's military defeated separatist, ethnic Tamil rebels in 2009.