Marine Le Pen

The second round contest pits centrist Emmanuel Macron, a 39-year-old former investment banker, against the far-right nationalist Marine Le Pen, 48.

Citizens in some overseas territories and many French expats abroad have begun voting.

The polls open in metropolitan France at 08:00 local time (06:00 GMT) on Sunday and close at 19:00 (17:00 GMT).

Polling stations will remain open in some big cities until 20:00 local time (18:00 GMT), with early estimates of the result due to be reported immediately after they close.

Mr Macron, a former banker, is seen as a political outsider, having never run an election campaign before.

After topping Sunday's vote, he is now favourite to win the run-off on 7 May.

It is the first time in six decades that neither of France's main left-wing or right-wing parties has a candidate in the second round.

With 97% of votes counted, Mr Macron stands at 23.9% with Ms Le Pen on 21.4%.

Their nearest challengers, centre-right François Fillon and hard-left Jean-Luc Mélenchon, fell behind, with just over 19% each.

Le Pen suggested France was not responsible for the wartime round-up of Jews who were sent to Nazi death camps. With just 13 days until the first round of voting in France's presidential election, her remarks have been met with widespread condemnation.