DAMASCUS - Syria's regime unleashed tanks and warplanes against rebels as battles raged on Wednesday, after France recognised the newly united political opposition and raised the prospect of arming its fighters.

Tanks shelled two refugee camps in southern Damascus, where fighting has intensified since the army put down a rebel assault in the southern belt of the capital city where anti-regime sentiment runs strong, a watchdog said.

Fighter jets bombed Maaret al-Numan, a northwestern town rebels captured last month in a major blow to the regime's ability to reinforce troops under attack in second city Aleppo, said the Syrian Observatory for Human Rights.

A day after France became the first Western nation to recognise the opposition National Coalition, the United States unveiled $30 million in extra humanitarian aid to those affected by the conflict as it endorsed the newly formed bloc.

Russian Prime Minister Dmitry Medvedev criticised countries siding with the opposition and insisted Moscow was staying neutral.

"We don't support anybody in this conflict, neither President Assad nor the rebels... but unfortunately, the point of view of some states is more one-sided," Medvedev told Finnish broadsheet Helsingin Sanomat.

President Francois Hollande said Paris recognised the coalition as "the sole representative of the Syrian people and thus as the future provisional government of a democratic Syria, allowing an end to the Bashar al-Assad regime".

The question of arming the rebels would now "have to be necessarily reviewed not only in France but in all countries which will recognise this government," said Hollande.

National Coalition chief Ahmed Moaz al-Khatib has called on world powers to arm Assad's foes, saying they desperately needed "specialised weapons" in order to "cut short the suffering of the Syrians and their bloodshed".

The United States said on Tuesday that the coalition was "a legitimate representative" of the Syrian people, but stopped short of recognising it as the sole representative.

Britain said it wants to see more evidence the grouping has strong support inside Syria before formally recognising it.

Announcing the latest US aid package on a visit to Australia on Wednesday, Secretary of State Hillary Clinton said the coalition's formation was "a good beginning".

"We have long called for this kind of organisation," Clinton said, but added Washington wanted to see the momentum maintained from the hard-won unity agreement reached in Doha, Qatar.

"Specifically we urge them to finalise the organisational arrangements to support the commitments that they made in Doha and to begin influencing events on the ground in Syria."

The French move came 24 hours after the coalition was recognised by the members of the Gulf Cooperation Council: Bahrain, Kuwait, Oman, Qatar, Saudi Arabia and the United Arab Emirates.

The Arab League stopped short of granting the bloc full recognition, only saying it saw the alliance as "the legitimate representative of the Syrian opposition".

The opposition agreed on Sunday to unify their fighting forces under a military council and to set up a judicial commission for rebel-held areas. They plan to form a provisional government.

On the ground, tanks moved on the Yarmuk Palestinian refugee camp and the neighbouring Damascus district of Tadamum following battles between the army and rebels in the area late on Tuesday.

Shells were fired into a second refugee camp east of Yarmuk on Wednesday morning, said the Observatory, though it did not specify whether they had been fired by the army or by rebels.

Elsewhere, fighter jets bombarded the rebel-held town of Maaret al-Numan in the northwestern province of Idlib.

"The air force has carried out two air strikes on the town of Maaret al-Numan," said the Observatory.

Rebels seized Maaret al-Numan on October 9, and the army has since waged an unrelenting but unsuccessful offensive to take back the town strategically located on the highway linking Damascus and second city Aleppo.

The jihadist Al-Nusra Front claimed responsibility, meanwhile, for a November 5 suicide car bomb attack on a military post in the central province of Hama that it said killed at least 200 pro-regime fighters.

At the time, the Britain-based Observatory put the toll from the blast at more than 50 dead.

The Observatory -- which relies on a network of activists, lawyers and medics -- said nationwide violence killed 189 people on Tuesday, including 90 civilians, 50 rebels and 49 soldiers.