THE THIRD IS THE ONLY WAY:

He was a rival of Hollande for the Socialist party's presidential nomination in 2011 but later become the president's campaign spokesman. On the right of the PS, he is an advocate of social democracy in the style of Germany and Scandinavia. In the past he has described himself as a "Blairiste" (after Tony Blair) and a "Clintonian" (after Bill Clinton) and talks of "economic realism" and "individual responsibility".

The UK's former Europe minister, Denis MacShane, a friend of Valls for a decade, told the Guardian: "He is the closest France has to a Tony Blair - a reformist, pro-growth social democrat not afraid to take on vested interests and challenge conventional statist thinking in France.

"He will come under pressure from the left but they have no answer to France's problems. It's do or die for Hollande but the departure of the Greens opens the way to France rethinking its energy policy and dropping some of the internal protectionism that slowed down growth. Valls is a tough, smart operator. If the French Socialist government can be saved he's the man to do it".

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