France has become the first European power to recognise Syria's new opposition coalition as the sole representative of its people.
France has also said it would look into arming rebels against President Bashar al-Assad, once the new coalition forms a provisional government.
The move came 24 hours after the coalition was recognised by the six member states of the Gulf Cooperation Council: Saudi Arabia, Bahrain, the United Arab Emirates, Oman, Qatar and Kuwait.
The United States and Britain have both signalled support for the coalition, but they stopped short of recognising it as a government-in-exile.
The diverse forces involved in the opposition coalition agreed on Sunday to unify their fighting forces under a supreme military council and set up a national judicial commission for rebel-held areas in Syria.
They plan to form a provisional government once the coalition has been widely recognised internationally.
"I announce today that France recognises the Syrian National Council as the sole legitimate representative of the Syrian people and as the future government of a democratic Syria making it possible to bring an end to Bashar al-Assad's regime," French President Francois Hollande told a news conference in Paris.
The French government, one of Mr Assad's harshest critics, has previously ruled out arming rebel forces, concerned that weapons could get into the hands of radical Islamists.
Mr Hollande suggested this stance may now change.
"On the question of weapons deliveries, France did not support it as long as it wasn't clear where these weapons went," he said.
"With the coalition, as soon as it is a legitimate government of Syria, this question will be looked at by France, but also by all countries that recognise this government."
France was the first country to formally recognise the Libya's transitional government as an alternative to former leader Muammar Gaddafi and at the time also broke ranks from its European partners.