"The United Nations Human Rights Council should adopt the recommendation of UN High Commissioner for Human Rights (UNHRC) Navi Pillay to create an independent international inquiry into war crimes and other serious abuses committed in Sri Lanka armed conflict," the New York-based HRW said.
"The Sri Lankan government has refused to address its role in the deaths of tens of thousands at the end of the country's brutal civil war," Brad Adams, Asia director of the HRW, said.
The report by Pillay, a South African of Indian Tamil origin, has concluded the Sri Lankan government has taken no significant steps to implement the recommendations on accountability of its own Lessons Learnt and Reconciliation Commission.
"National mechanisms have consistently failed to establish the truth and achieve justice. The High Commissioner believes this can no longer be explained as a function of time or technical capacity, but that it is fundamentally a question of political will," the report stated.
"The bottom line is that Sri Lanka has repeatedly refused to undertake investigations into crimes committed by its own forces, so it will be up to members of the UN Human Rights Council to take decisive action at the coming March session," Adams said.
Meanwhile, the Amnesty International also said that the Sri Lankan government’s targeting of critics persists at alarming levels, with more surveillance and harassment reported ahead of next month's UNHRC.