Here's what happened this weekend in France's presidential race

Here's what happened in the campaign on Saturday:

Scuffles broke out in a meeting room where Le Pen was due to speak on the island of Corsica, after security staff from her National Front party tried to eject around a dozen young Corsican nationalist protesters.

Tear gas was set off as punches were thrown, forcing staff to evacuate the room. Le Pen eventually had to hold the rally at a different location in Ajaccio, the capital of the Mediterranean island just off the coast of Italy.

The protesters had shouted "a Francia fora" ("France get out" in Corsican) and the separatist group Ghjuventu Indipendentista claimed responsibility for the disruption on Twitter.

"We can't accept the National Front candidate coming to our territory to spread her message, which is stamped with the seal of hate and straightforward anti-Corsicanism," the group wrote.

"We would never allow this party, whose former leader (Le Pen's fatherJean-Marie) demanded the death penalty for Corsican political prisoners, safe passage in our country."

The National Liberation Front of Corsica (FNLC) ran a brutal campaign of bombings and assassinations from 1976 to 2014. But today's nationalists are trying a peaceful approach to power, having performed strongly in regional elections in 2015.

Meanwhile, centrist frontrunner Emmanuel Macron detailed his priorities Sunday for his first few months in office if elected, as polls showed the unpredictable race tightening just two weeks before voting.

Macron, 39, told the Journal de Dimanche newspaper one of his first measures would be to pass a law setting new ethical standards for parliament, followed by related legislation that will cut the number of MPs by a third.

He also foresees a visit to Berlin and a tour of European capitals to drum up support for his plan to deepen economic integration in the eurozone, create a European border force and put in place greater protections for European industry.

Asked about a slight fall in support according to recent surveys, the independent centrist replied: "They show exactly what I feel: that nothing is decided yet. We are entering a crucial phase."

Several opinion polls show a tightening race between the top four candidates, with support for frontrunners Le Pen and Macron slipping back and conservative Francois Fillon neck-and-neck with Jean-Luc Melenchon of the far-left.

A poll by BVA Salesforce showed acid-tongued Melenchon jumping by four points in a week to 19 percent of first-round voting intentions -- the same as Fillon, who was once considered the favourite but has seen his ratings hit by a string of expenses scandals.

Ahead of the first round on April 23, Macron and Le Pen both hold 23 percent of voting intentions, according to the poll -- just four points ahead of their other two rivals in one of the most unpredictable French elections in decades.

The ethics authority of the bitterly divided Socialists called the party to order, deploring members who have declined to back their struggling candidate Benoit Hamon.

Former premier Manuel Valls is among senior Socialists who have opted instead to back Macron -- an attitude the ethics office criticised as contrary to "the principle of loyalty" and disrespectful of the public primary that saw Hamon emerge as candidate.

The BVA poll credited Hamon with just 8.5 percent of voting intentions, with both Macron and Melenchon having sapped his support.