Damascus: Arab nations have called on Syrian President Bashar al-Assad to swiftly give up power as his troops launched a fresh assault on rebels in Damascus and the second city Aleppo.
Fighting raged Sunday despite claims by the rebel Free Syrian Army that Assad's regime was "collapsing".
In a joint statement issued early Monday after their meeting in Doha, Arab League foreign ministers called on Assad to "renounce power," promising that he and his family would be offered "a safe exit".
"There is agreement on the need for the rapid resignation of President Bashar al-Assad," Qatar's Prime Minister Sheikh Hamad bin Khalifa Al-Thani told journalists after the Arab League meeting wound up in the small hours Monday.
The Arab League called on the Free Syrian Army rebels and the opposition to form a transitional government of national unity along with the "de facto national authority", without detailing who that authority might be.
The Arab nations also called for an extraordinary meeting of the UN General Assembly to work towards creating "security zones" and "humanitarian corridors" in Syria.
The United States declared Sunday that it would "hold accountable" any Syrian official involved in the release or use of the country's chemical weapons.
Fears have been rising in the West after reports that Assad might be prepared to use his arsenal of chemical weapons to save his embattled regime.
Sheikh Hamad urged Assad to "stop the destruction and the killings by taking a courageous decision" to cede the power he has wielded since 2000.
On the ground the feared regime forces led by Assad's brother used helicopter gunships Sunday in a new assault on rebels in Damascus, activists said, as clashes also raged in Syria's second city Aleppo.
Government forces mounted an offensive in the Damascus neighbourhood of Barzeh, triggering an exodus of residents, as a rebel commander appeared in a video saying the battle to "liberate" Aleppo had begun.
The official SANA news agency announced that government forces had "cleansed" the capital's Qaboon neighbourhood of "terrorists", the regime's term for rebel fighters.
And state television aired footage reportedly from Qaboon showing dead bodies and weapons, communications equipment and money it said was captured from rebels.
It said some of the rebels killed held identity cards from Jordan and Egypt, accusing foreign countries of training and sending in insurgents.
But it denied helicopter gunships were being used inside the capital.