"The FSA's brigades have staged a tactical withdrawal from Salaheddin in order to open a new front in Saif al-Dawla and Mashhad," said Wassel Ayub, who commands the Nur al-Haq Brigade.
"We had full control of the district last night, but then regime forces bombarded in an unprecedented way," Ayub said. "The situation is terrible, and we have decided to stage a tactical withdrawal."
Rebels and regime forces have engaged in fierce fighting over Salaheddin for more than two weeks. The rebels say they control some 50 percent of Syria's commercial capital.
On Wednesday, regime forces launched a fierce assault on Salaheddin, a district to which both rebels and the regime attribute great symbolic importance.
President Bashar al-Assad has appointed Wael al-Halqi as Syria's new premier, state television reported on Thursday.
"The president has signed Decree 298, appointing Wael al-Halqi as the new prime minister," the broadcaster reported.
Health Minister Halqi was appointed to replace Riad Hijab, whose defection to the opposition was announced on Monday.
Mr Hijab's was the highest-level defection from Assad's regime since the outbreak of a revolt almost 17 months ago.
Source: AFP