Around 250 members of the Syrian opposition were to meet Monday in Cairo for Arab League-sponsored unity talks to bridge differences and discuss a proposed transition plan for Syria.
The Arab League said the foreign ministers of France, Tunisia and Turkey had also been invited to the two-day conference, since these countries had previously hosted Friends of Syria meetings, DPA reported.
Representatives of the five permanent members of the United Nations Security Council were also expected to attend the conference, held on the outskirts of Cairo.
George Sabra, the spokesman of the opposition Syrian National Council (SNC), told dpa he expected the meeting to be "successful" and that two "important" documents would be issued at the end of it.
The first would be titled "The National Pledge to Syria" and the other would lay down "steps for the transitional period," he said.
On Saturday, world powers agreed during talks in Geneva that a Syrian transitional government, which would include members of President Bashar al-Assad's regime and the opposition, be set up to end the violence. The opposition says more than 14,000 people have been killed in the conflict since March 2011.
Syrian lawmaker Sharif Shehadeh, a staunch ally of al-Assad, told Syrian television that "the opposition's meeting in Cairo will not lead to anything."
"So far their repeated meetings have led to more killing," Shehadeh said.
Government forces shelled areas in the central province of Homs and the northern city of Aleppo on Monday, the Syrian Observatory for Human Rights reported, adding that Sunday's death toll had reached 100.
Activists said that more than 800 people had been killed over the past week. News coming from Syria cannot be independently verified as foreign journalists are still banned from entering restive areas.
Activists in the northern province of Idlib reported Monday that Turkish warplanes flew over the Turkish side of the border, after Syrian helicopters were seen hovering at low altitude on areas close to Turkey.
Lebanon's "Voice of Lebanon" radio station reported that Syrian forces had also opened fire toward the Jisr al-Kamar border crossing in the northern Lebanese area of Wadi Khaled at dawn on Monday.