France's Prime Minister Manuel Valls said on Tuesday a deal with Syrian President Bashar al-Assad to reach a political transition was impossible, but said Paris would back regional ground troops if they were to intervene against Islamic State militants.

President Francois Hollande on Monday said that French air strikes against the group in Syria would be necessary, a change in position after previously warning any such action could reinforce Assad.

"We will do nothing to strengthen the regime," Valls said in a speech to parliament to explain France's decision to launch reconnaissance flights and future action over Syria.

"The urgency, on the contrary, is to reach an agreement that definitively turns the pages of Assad's crimes ... with a man responsible for so many dead and crimes against humanity, no compromise or deal is possible."

France until now had only taken part in air strikes against Islamic State in Iraq, while also providing limited logistical support to rebels it deems moderate in Syria.
French PM Valls says no compromise with Syria's Assad possible | Reuters