By Sudip Kar-Gupta and Sarah White
PARIS - France's presidential election race looked tighter than it has all year on Friday, just over a week before voting opens as a new opinion poll put the four leading candidates only three percentage points apart.

The two highest scorers in the first round on April 23 will go through to contest a run-off on May 7. The race has been tightening for weeks, even though centrist Emmanuel Macron remains favorite.

According to the poll by Ipsos-Sopra Steria for Le Monde newspaper, Macron and far-right leader Marine Le Pen will tie on 22 percent each in the first round next Sunday, with the far-left's Jean-Luc Melenchon and conservative Francois Fillon on 20 and 19 percent respectively.

That made the most likely second-round scenario one that pits Le Pen against Macron. Consistently with most other surveys, the poll showed Macron winning that face-off with 63 percent of the vote.

Other polls have also been showing the race tightening during April, with the two leaders losing ground and the chasing pair, especially Melenchon, picking up support.

Melenchon's rise on the back of a strong performance in television debates is worrying investors, who fear his hostility to the European Union and plans to repeal pro-business labor reforms.

Polls show that Le Pen, who is also hostile to the EU and wants to dump the euro currency, have consistently shown that she will not win the presidency regardless of who she faces in the run-off.

However, some polls show that should Melenchon reach the second round, he could win there.

Friday's Le Monde poll had Macron beating Melenchon with 55 percent of the second-round vote, but it said Melenchon would beat Fillon and Le Pen, with the 65 year-old winning 60 percent in each case.

The poll was conducted on April 12 and 13 among 1,509 people.