An international war crimes prosecutor has resigned from her position on the UN’s investigative panel into human rights abuses in the Syrian civil war because she is so frustrated with its inability to hold criminals to account, it has emerged.

“I give up. The states in the Security Council don’t want justice,” Carla del Ponte told Swiss newspaper Blick over the weekend.

“I can’t any longer be part of this commission which simply doesn’t do anything.”

After six and a half years “everyone is bad” in the war-torn country, Ms del Ponte said. “The Assad government is committing terrible crimes against humanity and using chemical weapons. And the opposition, that is made up only of extremists and terrorists anymore” (Getty Images)

Ms del Ponte, the former Swiss Attorney-General, rose to prominence for her prosecution work in the international war crimes tribunals into the 1990s Rwanda and former Yugoslavia conflicts.

“Believe me, the terrible crimes committed in Syria I neither saw in Rwanda nor ex-Yugoslavia,” she said.

“We thought the international community had learned from Rwanda. But no, it learned nothing.”

In scathing comments Ms del Ponte criticised all sides in the complex six-year-old Syrian war, including the government of Syrian President Bashar al-Assad and the official rebel opposition.

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When she was first appointed to the independent Commission of Inquiry on Syria in 2012, “the opposition (members) were the good ones; the government were the bad ones,” she was quoted as saying.

But after six and a half years “Everyone is bad” in the war-torn country, she said.

“The Assad government is committing terrible crimes against humanity and using chemical weapons. And the opposition, that is made up only of extremists and terrorists anymore.”

The Security Council, she said, should have appointed a court similar to those for the Rwanda and Yugoslavian wars - a decision vetoed by permanent member Russia, which is a key backer of the Assad government.

“We have had absolutely no success” holding perpetrators of war crimes in Syria to account, she added.

“For five years we’ve been running up against walls.”

While the investigative panel has compiled thousands of interviews and other documentation of possible war crimes committed by all sides in Syria, the work was pointless without a tribunal, she added.

Ms del Ponte will leave her post in September, she said, sitting on the commission’s meetings until then.

In a statement the commission said it had been aware of Ms del Ponte’s plans since June and that its work “will continue”.

In pictures: Children play underground in Syria Show all 8 1 /8 In pictures: Children play underground in Syria In pictures: Children play underground in Syria A child plays in the ball pit at the 'Land of Childhood,' an underground playground in a besieged town in Syria Unicef In pictures: Children play underground in Syria Abdulaziz, 10, plays in the 'Land of Childhood' underground playground in Syria Unicef In pictures: Children play underground in Syria Boys look through a show window inside the tunnel that provides a safe passage for children between the two basements that form the 'Land of Childhood' in a besieged town in Syria Unicef In pictures: Children play underground in Syria Children play at the underground 'Land of Childhood' in a besieged town in Syria Unicef In pictures: Children play underground in Syria Two girls play at the 'Land of Childhood' underground playground in a besieged town in Syria Unicef In pictures: Children play underground in Syria Children on the ride on a ferris wheel at the 'Land of Childhood', an underground playground in a besieged town in Syria Unicef In pictures: Children play underground in Syria Seven-year-old Massa at the "Land of Childhood" underground playground in a besieged town in Syria Unicef In pictures: Children play underground in Syria Children wait in line to buy sweets at the 'Land of Childhood,' an underground playground in a besieged town in Syria Unicef

With Ms Del Ponte’s departure there are now just two members left on the commission - Thai professor and former human rights investigator Vitit Muntarbhorn left in 2016 to become the UN’s first-ever independent expert investigating violence and discrimination based on sexual orientation.

In recent months the commission’s relevance has been called into question by the UN’s General Assembly, which - faced with a deadlocked Security Council - in December 2016 created a separate investigative body designed at preparing legal cases for the most serious human rights violations in Syria’s bloody civil war.

Efforts by Turkey, Russia, Iran and the US to broker talks and ceasefires have had some success so far in 2017, although reports of sporadic fighting continue, and extremists Isis continue to roam Syria’s northeast.