COLOMBO : Sri Lanka vowed Tuesday it will not cooperate with a United Nations war crimes investigation confirmed by the UN human rights chief, describing the probe as setting a “dangerous precedent.”Sri Lanka told the UN Human Rights Council in Geneva that it would not assist the investigation into widespread allegations of rights abuses and mass killings of civilians in the final stages of its decades-long separatist war. UN rights chief Navi Pillay on Tuesday formally announced the setting up of the war crimes investigative panel in line with a United States-initiated resolution passed in March.Sri Lanka’s permanent representative to the UN in Geneva, Ravinatha Aryasinha, said the UN-mandated investigation was harmful to his country and its reconciliation efforts. “Requesting the Office of the High Commissioner for Human Rights to undertake an investigation with ‘assistance from relevant experts’ sets a dangerous precedent,” Aryasinha said in a statement released to reporters in Colombo.International rights groups say up to 40,000 civilians were killed by troops in the final stages of Sri Lanka’s Tamil separatist war that ended in May 2009 with the elimination of the top Tamil rebel leadership. Colombo strongly denies that its troops killed any civilians, but instead says the defeated Tamil Tiger guerrillas used civilians as a human shield. Rights groups have accused both sides of targeting civilians. Aryasinha’s remarks came after Pillay urged Colombo to cooperate with the probe. “I encourage the government to take this opportunity to cooperate with a credible truth-seeking process,” she said at the opening of the 26th session of the Council. She said the investigation was expected to “advance accountability, and thus reconciliation,” but has not formally named members of the investigative body. The UN has set aside a budget of nearly $1.5 million for the investigation and the office of the High Commissioner is expected to present a final report by March 2015.