Leading rights groups urged Nepal on Monday to drop plans for a blanket amnesty over thousands of killings and other atrocities committed during the country's ten-year civil war.
More than 16,000 people died in the conflict between Maoist rebels and the state, which ended in 2006, and more than 1,000 are still missing.
The parliament is setting up a Truth and Reconciliation Commission to investigate wartime killings, torture and forced disappearances and is debating proposals to grant an amnesty for abuses by government and rebel forces.
Human Rights Watch and the International Commission of Jurists released a joint statement calling on political leaders to fulfil a commitment made in the post-war peace agreement to prosecute violations of international law.
"Amnesty for gross human rights abuses -- such as torture, including rape and enforced disappearance -- would violate international law," said Frederick Rawski, of the Geneva-based ICJ.
"Amnesty for these crimes would also contradict well-established Nepal Supreme Court jurisprudence and the government's own public commitments at the UN Human Rights Council."
New York-based HRW released a report in 2010 compiled with Nepali rights group Advocacy Forum documenting 62 cases of killings, disappearances, and torture carried out between 2002 and 2006.
Most were committed by state security forces but some were blamed on the Maoist People's Liberation Army, and the report said both forces were using their power to impede investigations.
"Victims are entitled to both knowledge of what happened and to effective remedy and reparation, including the prosecution of those responsible," said John Sifton, Asia Advocacy Director of HRW.