Asked if he thought Assad was directly responsible for Hariri's killing in Beirut last February, Khaddam told Britain's Sky Television in an interview broadcast on Thursday: "In my belief, yes, my personal belief is that he ordered it."

"But at the end of the day there is an investigation. They must give the final decision," he added.

Khaddam, who moved to Paris after resigning in June, has said in interviews since December that Assad had threatened Hariri shortly before he was killed in a car bombing on February 14. Assad has denied the charge.

In December, Khaddam told Arabiya television that the killing of Hariri could not have been carried out by Syrian agents without Assad's participation.

Assad is under intense international pressure to cooperate with a U.N. probe into the killing of Hariri. Syria said on Thursday it would not allow investigators to meet Assad.

Khaddam has said he seeks the overthrow of the Syrian government, and Syrian officials call him a traitor. Asked if he would use the same word to describe Assad, he said: "Yes, I call him a traitor."

"Corruption in Syria is so widespread within the closed circle around the president. He's practised corruption so much that you see that his cousins control everything. And as far as foreign policy is concerned, his policy is causing humiliation to Syria," he said.

Source: Reuters