A group of US diplomats have used a State Department channel for dissident views to criticize President Barack Obama’s Syria policy, a spokesman confirmed Thursday.

A group of US diplomats have used a State Department channel for dissident views to criticize President Barack Obama's Syria policy, a spokesman confirmed Thursday.

The official would not discuss the contents of the cable, but the New York Times and Wall Street Journal said the dissenters call for US strikes against the Syrian government.

"We are aware of a dissent channel cable written by a group of State Department employees regarding the situation in Syria," State Department spokesman John Kirby told AFP.

"We are reviewing the cable now, which came up very recently," he added.

The department's "Dissent Channel" allows diplomats who disagree with an official policy line to register their concerns with senior staff without fear of retribution.

Kirby said US Secretary of State John Kerry "values and respects" the device, but would not be drawn on whether he believes this specific complaint has merit.

According to the New York Times, which said it had seen a draft of the memo, the diplomats call for the US military to directly target the Syrian governmnet.

The memo, according to the Times, calls for "a judicious use of stand-off and air weapons" -- in other words cruise missiles, drones and perhaps direct US air strikes.  

The Journal report said the memo was signed by 51 mid- to high-level senior State Department officials.