Fighting raged Wednesday between Syrian troops and rebels on the outskirts of the capital Damascus, activists said, as more Palestinian refugees fled the country for Lebanon, DPA reported.
State-run media confirmed the clashes, saying "the terrorists" - referring to rebels - were being confronted by government troops.
In the northern province of Aleppo, at least 11 fighters died and 20 were wounded in a car bombing, Rami Abdel Rahman, the head of the opposition Syrian Observatory for Human Rights, told dpa.
President Bashar al-Assad's troops and rebels have been fighting in Aleppo, Syria's biggest city, with insurgents claiming major gains.
The Observatory said battles near Damascus were focused on the rebel-held towns of Daraya and Ghotta.
Government troops and rebels also engaged in fierce clashes in al-Tadamun district and the Palestinian refugee camp of al-Yarmouk south of Damascus, said the Britain-based organization.
Opposition forces have been fighting government troops in and around Damascus, raising the possibility that al-Assad could lose his hold on the capital.
News from Syria is hard to verify as authorities have barred most foreign media from the country since a pro-democracy uprising started in March last year.
Meanwhile, Lebanese media reported that Syrian Interior Minister Mohammed al-Shaar had been admitted to the American University Hospital in central Beirut for treatment.
Hospital staff could not confirm the report, but unusual security was in place in nearby areas.
A Lebanese government official told dpa that al-Shaar was already in the hospital. The official, who requested anonymity, declined to give details.
Activists said al-Shaar had suffered injuries from twin blasts outside the Interior Ministry on December 13.
Al-Shaar narrowly escaped death in July when a massive bombing in Damascus claimed the lives of four other top security officials, including the defence minister and al-Assad's brother-in-law.
In Geneva, the UN appealed for international donations of 1.5 billion dollars to help people in Syria and refugees.
The UN High Commissioner for Refugees office said it needed 1 billion dollars for the 1 million refugees expected to have left Syria by mid-2013, up from the current 525,000.
The UN Office for the Coordination of Humanitarian Affairs appealed for an additional 500 million dollars to provide food, shelter and medical help inside Syria, and to rebuild infrastructure.
The Lebanese-Syrian border saw a new influx of Palestinian refugees displaced by fighting in al-Yarmouk, according to Lebanese sources.
Around 60 Palestinian families crossed into Lebanon Wednesday, a Lebanese border guard told dpa.
They join some 2,000 Palestinians who have entered Lebanon in the past three days, according to estimates by the UN agency for Palestinian refugees and the Lebanese General Security Department.
Palestinian President Mahmoud Abbas appealed to UN chief Ban Ki-moon to help relocate the refugees from Syria to the Palestinian territories, the official Palestinian Wafa news agency reported.
Israel, which occupies and controls the borders of the Palestinian territories, is not expected to agree to the return of any large number of refugees to either the West Bank or the Gaza Strip.
The UN Relief and Works Agency said at least half of al-Yarmouk's registered population of 150,000 had fled the violence.
A Swedish newspaper meanwhile reported that al-Assad's troops have used cluster bombs in an area near the Turkish border.
The Dagens Nyheter daily, citing a witness in Syria, said four people were killed and a dozen wounded in an attack a week ago in the town of Marea, about 30 kilometres from the border with Turkey.
In October, human right groups accused al-Assad's government of dropping internationally banned cluster bombs on restive areas.