Damascus: Rockets killed at least 18 people on Wednesday in regime-held areas of Syria’s main northern city of Aleppo, a focal point of the 33-month conflict pitting loyalists against rebels.

On the diplomatic front, a US official said Washington had reached out to Islamist rebel groups in its quest for a negotiated settlement but not to groups it has blacklisted for links to Al Qaida.

The multiple rocket attack on the Furqan and Meridian districts of Aleppo, the country’s pre-war commercial capital, also wounded at least 30 people, the Syrian Observatory for Human Rights said.

State television said at least 17 people were killed.

Aleppo has been one of the main battlegrounds of the conflict since rebels seized large swathes of the city in an offensive launched in July last year. But despite persistent skirmishes between the loyalist and rebel forces, the front lines have changed little in more than a year, reflecting a stalemate across much of war-torn Syria.

The international community has become increasingly alarmed about the potential spillover into neighbouring countries of the war that has killed an estimated 126,000 people since it erupted in March 2011.

Meanwhile, Deputy State Department spokeswoman Marie Harf said Washington was engaged with a “broad cross-section of Syrian people and political and military leaders in the opposition, including a variety of Islamist groups” ahead of a US- and Russian-backed peace conference planned for January.

Harf said the contacts were “in response to a reality that the opposition is made up of a number of groups, some are Islamist groups, and that in order to get a political solution here, because there is no military solution, we need to get these groups to buy into the notion that there should be a [political] solution.”

The planned peace conference in Geneva is envisioned as a follow-up to a previous meeting in the Swiss city in June 2012, at which the government and the opposition agreed on the formation of a transitional government without specifying what role, if any, Al Assad would have in it.

Information Minister Omran Al Zohbi insisted on Wednesday that Al Assad would remain president and lead any transition agreed at the Geneva talks.