The possibility of Marine Le Pen winning the French presidential elections is a worrying prospect for the European Union and needs to be prevented by the French people, Luxembourg's Foreign Minister Jean Asselborn said on Monday.

"I am very worried, I hope that we won't get Le Pen as French president," Asselborn said before a meeting with fellow European ministers in Luxembourg. "It would not only be a break away from the core values of the EU, it would totally change its course. The French need to prevent this."

Emmanuel Macron, the incumbent centrist president, and Le Pen came out on top in the 12-candidate first round. He received more than 27% and she came in second with about 23%. The hard-left Jean-Luc Melenchon was third with nearly 22%.

Speaking about the elections, influential Socialist politician Segolene Royal said the inability of France's fractured left-wing to unify behind a candidate was to blame for the success of the far-right Marine Le Pen in the first round of the French presidential election.

Several candidates on the left of the political spectrum apparently ran to serve their egos, despite poor poll ratings, and ended up with less than 5% of the vote on Sunday, Royal told BFMTV on Monday.

"If they had withdrawn from the race, we would have Jean-Luc Melenchon in the second round and France would enjoy a real, fundamental debate, a real choice between values and strategies," she said.

According to the French Interior Ministry, the veteran leftist Melenchon was only about 1.5 percentage points behind Le Pen after almost all the votes had been counted, narrowly missing out on a place in the run-off on April 24.

In the 2007 presidential election, Royal was the Socialist candidate in the run-off against the conservative Nicolas Sarkozy, who eventually became president. She is the former partner of the François Hollande, who was president from 2012 to 2017. Royal is still very well known in France and a media presence.