France said on Sunday it had launched its first air strikes against Islamic State in Syria in an act of "self-defence" to stop the militant group from carrying out attacks inside France.

Prime Minister Manuel Valls said on BFM-TV that the strikes targeted Islamic State trainingcentreswhere militants were being prepared for carrying out attacks in France.

"We are hittingDaeshbecause this terroristorganisationprepares its attacks against France from Syria. We are acting in self-defence," Valls said, using an Arabic name for Islamic State.

The announcement came a few hours before President Francois Hollande was to join world leaders for the start oftheUnitedNations general assembly in New York.

"Ourcountry thusconfirms its resolute commitment to fight against the terrorist threat represented byDaesh(Islamic State). We will strike each time that our national security is at stake," the French Presidency said in a statement.

Islamist militants carried out a number of attacks in France this year, including oneonthe Paris office of satirical weekly Charlie Hebdo in which 12 people died.

A source in the presidency said the strikes were carried out early on Sunday morning.

The United States is leading a coalition carrying out air strikes in Iraq and Syria. France had so far only taken part in strikes in Iraq, fearing such action against the group in Syria could strengthen Syrian President Bashar al-Assad.

But earlier this month, France began reconnaissance flights over Syria to gather information on Islamic State positions.

The French Presidency said this information was used to carry out Sunday's strikes, which had been launched in coordination with its partners in the U.S.-led coalition.

France was ready to join air strikes on Assad's forces in Syria in 2013 before U.S. President Barack Obama backed off the plan.

France also on Sunday called for a "global solution" to the Syrian crisis, saying it supported U.N.specialenvoy StaffandeMistura's initiative to work towards a political transition for the country.

France's foreign minister Laurent Fabius said on Saturday that Bashar al-Assad could not play any role in a political transition, because this would not be credible to the Syrian people after so many deaths at the hands of his government.