Fillon set to face Le Pen

Francois Fillon, a conservative reformist promising to shrink the French state, on Sunday clinched the rightwing nomination for next year's presidential election with a resounding victory over his rival Alain Juppe.

Ex-prime minister Fillon, 62, will now become a favourite to be France's next leader after winning the US-style primary to pick the nominee of the Republicans party and its allies.

Near-complete results showed him winning 66.5 percent of the vote, with ballots counted from 9,915 polling stations out of 10,229.

The French presidential vote is seen as a key test for mainstream political parties after the success of Donald Trump and the Brexit campaign in Britain, both of which harnessed anti-elite anger.

Fillon will face fierce competition in the two-round election in April and May from far-right leader Marine Le Pen, the anti-establishment candidate hoping to emulate Trump's shock victory in the US.

Fillon said a win for the anti-EU Le Pen would spell "bankruptcy".

Two surveys late Sunday put Fillon ahead of Le Pen in the first round of the election, with the left-wing candidates trailing further behind.

But the race is seen as highly unpredictable after a year of political upsets and uncertainty about the impact of independents and the Socialist party candidate.

Socialist President Francois Hollande has yet to announce whether he will try to defy his historically low approval ratings by running for a second term.

Prime Minister Valls has not ruled out challenging his boss in a left-wing primary set for January, telling the weekly Journal du Dimanche he wanted to dispel the idea "that the left has no chance" of retaining power.