A United Nations team of war crimes investigators will not probe air strikes by foreign countries in Syria, its chairman said on Wednesday, despite concerns that some attacks by foreign militaries could have violated the laws of war.

The U.N. Commission of Inquiry on Syria is not intended to investigate air strikes in Syria by foreign nations, Chairman Paulo Pinheiro said.

“It is not our mandate to investigate the behavior of powers involved in the crisis of Syria,” Pinheiro told the Thomson Reuters Foundation in a telephone interview.

It would not probe potential cases of violations of international human rights law involving nations conducting military strikes in Syria, he said.

“There is no possibility that we will investigate the American air strikes or French or British or Russian,” he said.

The decision reflected a desire not to meddle into the affairs of powers outside Syria as well as limited means at the group’s disposal, Pinheiro added.

With the rapid expansion of territory controlled by the militant group ISIS, nations including the U.S., France, Britain and Russia have carried out air strikes on targets in Syria.

Some observers have cited instances that disproportionately hit civilians and civil infrastructure, and Pinheiro and his three co-commissioners have repeatedly cautioned powers to follow the laws of war.

Embodied in the Geneva Conventions, the rules require warring parties to distinguish between military and civilian targets, such as schools and hospitals, and carry out operations in a way that is proportional to the perceived threat.

U.S. officials said in November they did not dispute human rights activists’ allegations that Russian bombs and missiles have hit Syrian mosques, hospitals and other civilian infrastructure, killing hundreds of people.

Last Update: Wednesday, 20 May 2020 KSA 09:49 - GMT 06:49