The UN's new envoy to Syria has said that president Bashar Assad's regime should realise that the need for change is both "urgent" and "necessary" and that it must meet the "legitimate" demands of the Syrian people.
Lakhdar Brahimi's comments in an interview with al-Arabiya television came as Syrian warplanes and ground forces pounded the country's largest city, Aleppo, with bombs and mortar rounds while soldiers clashed with rebels in the narrow streets of its old quarter, according to activists.
The latest violence shows that government troops are still struggling to regain full control of the city from the lightly armed rebels nearly five weeks after they stormed their way into it in a surprise offensive. Activists said rebels also captured an air defence facility in the east of the country near the border with Iraq.
"The Syrian government realises more than me the extent of the suffering endured by the Syrian people," Mr Brahimi told al-Arabiya on his first day as the new UN envoy in Syria, after replacing Kofi Annan who quit after his six-point plan including an April 12 ceasefire failed to stop the bloodshed.
Speaking in New York, he said: "The need for change is urgent and necessary. The Syrian people must be satisfied and their legitimate demands are met."
A former Algerian foreign minister and a seasoned international trouble-shooter, Mr Brahimi said he enjoyed the "full and clear" support of the UN Security Council.
He also called for an end to the violence but acknowledged that he does not have a set of preconceived ideas on how to resolve the Syrian conflict. "We will try to overcome the obstacles that Kofi Annan faced," he added.
The Syrian conflict has its roots in mostly peaceful street protests that started in March last year. It has since morphed into a civil war, with at least 20,000 people killed so far, according to rights activists.
The Britain-based Syrian Observatory for Human Rights said the clashes in Aleppo were concentrated in several tense neighbourhoods - Hanano, Bustan al-Qasr, Sukkari and Maysar. It reported injuries and damage to buildings.
Another activist group, the Local Coordination Committees (LCC), said the government was making heavy use of warplanes in attacking rebel areas.