Syrian opposition leaders will meet in Paris this month, French Foreign Minister Laurent Fabius said on Sunday, decrying an "abominable" situation in which he said 100 people a day were being killed in an uprising against President Bashar al-Assad.

"The situation is horrific and Bashar must go as fast as possible," Fabius said.

"There will be a meeting of the coalition in Paris in a few days, on the 28th. It's a coalition recognised by more than 100 countries, led by extremely respectable people who simply want to restore democracy in Syria," he said.

Syria's opposition leaders met in Istanbul on Saturday to launch their second bid to form a transitional government.

Agreement among the National Coalition, a grouping formed last November, could help address international concern about the risk of Syria disintegrating along ethnic and sectarian lines if Assad falls.

Failure would highlight the divisions in the coalition, formed with Western and Gulf backing in Qatar, and undermine that support.

Fabius, interviewed on radio station Europe 1, said that the Paris meeting later this month would involve the "main backers" of the opposition coalition.

France has been pressing hard for an end to a 22-month conflict in which 60,000 people have been killed, according to United Nations estimates. "This is an abominable situation, with sadly around 100 people killed a day," Fabius said.

Syria's foreign minister said on Saturday any discussion of Assad's future was "unacceptable", a week after an international envoy said the president should not be part of a transitional government. – Reuters