Former chief UN prosecutor Carla del Ponte said Monday that the International Criminal Court should be called in to probe alleged war crimes in Syria and bring the perpetrators to justice.
Issuing a report by a UN commission of inquiry that found war crimes by both government forces and rebels were spiralling amid an increasingly radicalised and sectarian conflict, del Ponte said it was time to act.
"We suggest the International Criminal Court. We can't decide, but we are pressuring the international community to act, because it's time to act," said del Ponte, a member of the Independent International Commission of Inquiry.
"It's time to react. After two years, it's incredible that the Security Council hasn't made a decision," she told reporters in Geneva as the team prepared to submit a list of perpetrators who should face justice.
"Justice must be imminent, urgent. The number of victims is increasing day to day. Justice must be done."
The decision to refer the conflict to the ICC lies with the UN Security Council, where there are deep rifts between Western members and Russia, a longstanding ally of Syria's regime, plus China.
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China has backed Russia in vetoing Security Council resolutions that would have put greater pressure on President Bashar al-Assad's regime. Beijing has also repeatedly urged dialogue to end the violence.
Speaking by telephone from his homeland Brazil, the commission's chief Paulo Pinheiro refused to be drawn on the names on the list of individuals and Syrian military and rebel units accused of war crimes.
The commission is due to submit the list to the UN's human rights office next month, potentially setting the wheels of international justice in motion, but has said it will not make it public.
Del Ponte gained renown for her tough stance as the UN's top prosecutor investigating war crimes in Rwanda and the former Yugoslavia.
"I'm not the prosecutor dealing with this case. Unfortunately," she said Monday.
The commission was set up in 2011 at the behest of the UN Human Rights Council.
Syria has been embroiled in conflict since Assad's regime launched a brutal crackdown on protests that erupted in March 2011. The United Nations says about 70,000 people have been killed.
"We don't take sides. We must investigate the crimes committed by everyone involved in the conflict in Syria," said Pinheiro.
Unable to gain access to Syria -- the government has failed to respond to its request for entry -- the commission has interviewed over 1,500 refugees and contacted individuals inside the country to produce its reports.
-- Conflict increasingly 'radicalised and militarised' --
A similar report in August also said both sides were responsible for war crimes, but that government forces carried more blame.
Since then, the violence had spiralled, the commission said Monday.
"The conflict has become increasingly sectarian, with the conduct of the parties becoming significantly more radicalised and militarised," it said.
Pinheiro said well-armed foreign fighters, honed in conflict zones such as Libya or Afghanistan, were driving the radicalisation of anti-regime militias.
Most of the rebels are Sunni Muslims, while the ruling clan and many of its most fervent supporters are from the minority Alawite sect, an offshoot of Shiite Islam.
"Government forces and affiliated militia committed the crimes against humanity of murder, torture, rape, enforced disappearance and other inhumane acts," the report said.
But the commission also lambasted the rebels.
"Anti-government armed groups have committed war crimes, including murder, torture, hostage-taking and attacking protected objects. They continue to endanger the civilian population by positioning military objectives inside civilian areas," it said.
"Where armed groups carried out bombings in predominantly civilian areas, it had the effect of spreading terror and amounted to the war crime of attacking civilians."
But the report said the regime remained the major perpetrator.
"The violations and abuses committed by anti-government armed groups did not, however, reach the intensity and scale of those committed by government forces and affiliated militia."