DAMASCUS - Syrian forces backed by helicopter gunships and tanks launched a deadly assault on parts of Damascus on Wednesday, activists said, as the regime battles to stamp out rebel resistance in the capital.

At least 37 people were reported killed in Damascus alone, a day after a top minister hinted that the embattled regime was ready to discuss President Bashar al-Assad's exit in any talks on ending the brutal 17-month conflict.

Fighter jets and artillery hit Aleppo and heavy shelling was reported in Daraa, the birthplace of the uprising, and the eastern town of Deir Ezzor while rebels claimed they seized parts of a town on the Iraq border, a watchdog said. The army attacked several areas where anti-regime sentiment is strong in and around the southwest of Damascus, including heavy shelling, helicopter fire and mass arrest sweeps, the Syrian Observatory for Human Rights said.

In the deadliest operation, the army raided the southwestern district of Kafr Sousa, killing at least 24 civilians, it said, while a pro-opposition journalist was also killed during a raid on his home in Damascus.

As the fighting raged, the United States and France again pushed for Assad to stand down quickly after a top Syrian official said Damascus was ready to discuss his exit as part of a negotiated settlement to the conflict.

"As far as his resignation goes - making the resignation itself a condition for holding dialogue means that you will never be able to reach this dialogue," Deputy Prime Minister Qadri Jamil said in Moscow. But he added: "Any problems can be discussed during negotiations. We are even ready to discuss this issue." Moscow, however, bluntly told the West not to meddle in Syria after US President Barack Obama hinted at possible military action if Damascus resorted to its chemical weapons arsenal.

"There should be no interference from the outside," Foreign Minister Sergei Lavrov said after his talks with Jamil. "The only thing that foreign players should do is create conditions for the start of dialogue."

But Washington was unimpressed by the apparent overture from Damascus. "We still believe that the faster Assad goes, the more chance there is to quickly move on to the day after," US State Department spokeswoman Victoria Nuland said, dismissing Jamil's comments as "nothing terribly new". At least 84 people were killed nationwide Wednesday, according to the Observatory, which says a total of over 23,000 people died since the uprising began in March 2011.

In Aleppo, fighter jets struck near a missile depot, and shelled several other areas of the city that has become the key battleground since fighting first erupted there a month ago, the Observatory said. It also said rebel fighters had seized an intelligence office and checkpoints in the eastern town of Albu Kamal on the Iraqi border, although regime forces remained largely in control.

At least 11 civilians were also killed in Daraa in the far south.

The United Nations puts the death toll at 17,000 and says hundreds of thousands more have fled to Syria's neighbours while another 2.5 million still in the country are in desperate need of aid. The conflict has spilled over again into neighbouring Lebanon, with ten dead in clashes that first erupted late Monday between pro- and anti-Damascus regime supporters in the northern port city of Tripoli.

"As the crisis in Syria continues to deteriorate, the situation in Lebanon has become more precarious and the need for continued international support to the government and the Lebanese armed forces increasingly important," said UN under secretary general Jeffrey Feltman. The international community has struggled to end the Syria conflict in the face of divisions between the West and Damascus's traditional allies in Moscow and Beijing. Political sources in Damascus said Jamil was sent to Moscow to discuss a possible plan for a presidential election in which all candidates would be allowed to stand, including Assad.

Obama had put Assad's regime on notice Monday that although he had not ordered military action "at this point," Washington would regard any recourse by Damascus to its chemical arsenal as crossing a "red line."

French Prime Minister Jean-Marc Ayrault meanwhile said there was no question of Paris becoming directly involved in military action without UN backing but acknowledged his country was providing rebels with "non-lethal" military aid. The West has refused to arm the rebels - at least openly - but weekend press reports said British and German spies were also helping them.