The defection of a Syrian general who is a personal friend of President Bashar al-Assad gave a huge boost to anti-government rebels as Western and Arab states met them in Paris on Friday to help prise Assad from power.

Manaf Tlas, a brigade commander in the Republican Guard who attended military college with Assad and fled to Turkey this week, was on his way to Paris, where his father, Assad's father's defense minister, has also taken up residence, a close family friend told Reuters.

There was no immediate sign that Tlas would throw in his lot with the rebels and an opposition source said he had no plans to attend Friday's meeting.