Asked how he would evaluate Syria’s cooperation, Mehlis said: "If I would answer this question truthfully, the Security Council will kill me on Tuesday afternoon.

"We are an instrument of the Security Council…they deserve to be informed first."

Mehlis also confirmed he would step down at the end of his six-month mandate by mid-December, but said he would help the commission until the United Nations names his successor if the Security Council agreed next week to extend the inquiry.

Lebanon has asked the United Nations earlier this month to renew the commission’s mandate for six months beyond December 15. The inquiry was officially launched in June.