United Nations monitors reported on Monday Syrian helicopters firing on two rebel towns north of the city of Homs, a spokeswoman for the observer mission said.   

"U.N. observers reported heavy fighting in Rastan and Talbiseh, north of the city (of Homs), with mortar shelling as well as firing from helicopters, machine guns and smaller arms," Sausan Ghosheh said in a statement.

The new leader of the Syrian National Council Abdelbaset Sayda called on Syrian President Bashar Assad to step down in favor of his deputy Farouk al-Sharaa, according to the Turkish news agency Anadolu.

International mediator Kofi Annan voiced deep concern on Monday at the latest violence in Syria, citing shelling of the opposition stronghold of Homs and reports of the use of mortar bombs, helicopters and tanks in al-Haffa, near the coast.   

"There are indications that a large number of civilians are trapped in these towns," Annan's spokesman Ahmad Fawzi said in a statement issued in Geneva.

Annan demanded that U.N. military observers be allowed into al-Haffa immediately.

As for France, it congratulated the new leader of the Syrian National Council, Kurdish activist Abdelbaset Sayda and called on him to unite the Syrian opposition “with a spirit of openness and unity”, according to the French Ministry of Foreign Affairs.  

Israel’s Deputy Chief of Staff Yair Naveh announced that Syria has the “largest arsenal of chemical weapons in the world”, stressing that these weapons could be used against Israel.

In the field, 74 people were killed in violence and clashes across Syria on Monday, according to the Human Observatory for Human Rights that reported that shelling was renewed on cities surrounded by the regime’s forces in the provinces of Homs and Lattakia.        

SANA news agency reported that Syrian authorities foiled an attempt by “an armed terrorist group” to blow up a booby-trapped car loaded with huge amount of explosives in an area located near the region of Jermana in rural Damascus on Monday at dawn.       

The agency said that the explosive device weighed about 700 kg, adding that a delegation of international monitors inspected the booby-trapped car.          

An “armed terrorist group” also blew up a gas transmission line extending from the field of the Furat Petrolium Company in Deir al Zour to Homs using an explosive device, resulting in the leakage of 400,000 m3 of gas, according to SANA.