BEIRUT (AP) - The chief U.N. observer in Syria says his mission is irrelevant without a political process seeking to end the country's civil war.

Maj. Gen. Robert Mood told reporters in Damascus Thursday that "we are not on the track for peace," citing intense fighting in and around the capital this week.

Mood's comments come a day after a rebel bomb attack struck the heart of the regime of President Bashar Assad, killing the defense minister, his deputy and a former defense minister.

The U.N. Security Council is to vote Thursday on whether to renew the monitoring mission, which expires Friday.

Syria's 16-month crisis has evolved into a civil war, with scores of rebel groups fighting to topple Assad's regime.