Western and Arab countries opposed to President Bashar Assad agreed at talks in Qatar on Saturday to give urgent military support to Syrian rebels fighting for his overthrow, and to channel it through a Western-backed rebel military command.

Ministers from the 11 main countries which form the Friends of Syria group agreed "to provide urgently all the necessary materiel and equipment to the opposition on the ground, each country in its own way in order to enable them to counter brutal attacks by the regime and its allies".

U.S. Secretary of State John Kerry, who attended the meeting, said participants agreed that military support for the Syrian opposition would be according to each member country's initiative.

Besides the US and Qatar, the Friends of Syria include Britain, France, Germany, Italy, Jordan, Saudi Arabia, Turkey, Egypt and the United Arab Emirates.

The ministers also condemned "the intervention of Hezbollah militias and fighters from Iran and Iraq", demanding that they withdraw immediately.

Guerrillas from Lebanon's Shi'ite pro-Iranian Hezbollah organization spearheaded the recapture of the strategic border town of Qusair from mainly Sunni Muslim rebels two weeks ago.

Hezbollah and Shi'ite Iraqi gunmen have also been fighting around the Shi'ite shrine of Sayyid Zainab south of Damascus, while Iranian military commanders are believed to be advising Assad's officers on their counter-offensives against the rebels.

The ministers said the growing sectarian nature of the conflict and the foreign interventions "threaten the unity of Syria (and) broaden the conflict" across the region. They also expressed strong concern at the increasing presence of "terrorist elements" and growing radicalization in Syria.