PARIS -- France's top diplomat is leaving his post to be named chief of the constitutional Council, France's top court making sure that bills comply with the constitution.

French President Francois Hollande formally proposed the nomination of Foreign Minister Laurent Fabius to the constitutional Council in a statement Wednesday. The 69-year-old Fabius had been in office since 2012.

His successor is not known yet but a government reshuffling is expected in the coming days. Environment and Energy Minister Segolene Royal and former Prime Minister Jean-Marc Ayrault, two of France's most experienced Socialist figures, are widely considered as favourites to take the position.

Fabius told iTele television his one regret as foreign minister is that "the world didn't follow" France's position on Syria. Paris was pushing for a military intervention with the U.S. against Syrian President Bashar Assad's regime during the summer of 2013.

He said "we should have had taken action."

Fabius also voiced France's tough position during the nuclear negotiations with Iran.

For years Fabius also tried to help revive Israeli-Palestinian peace talks, as a strong supporter of the "two-state solution." He recently said France will recognize a Palestinian state if the negotiations face a deadlock.

His international stature soared last December, when almost 200 countries reached an agreement at the U.N. climate conference in Paris. Fabius, host of the two-week talks, was praised for his patience and listening skills. When he gaveled the deal they gave him a standing ovation.

"It's rare in life to be able to move things forward at the planet level," a visibly moved Fabius said.