Centrist French presidential candidate Emmanuel Macron extended his lead in the polls over his far-right rival Marine Le Pen yesterday, the final day of a tumultuous election campaign that has turned the country's politics upside down.

The election is seen as the most important in France for decades with two diametrically opposed views of Europe and France's place in the world at stake.

The National Front's Le Pen would close borders and quit the euro currency, while independent Macron, who has never held elected office, wants closer European cooperation and an open economy. The candidates of France's two mainstream parties were both eliminated in the first round on April 23.

Four new polls showed Macron on track to win 62 percent of the votes in the second round compared to 38 percent for Le Pen, his best score in a voting survey by a major polling organisation since nine other candidates were eliminated in the first round on April 23. A fifth poll showed him on 61.5 percent.

His challenger Marine Le Pen waves to the crowd as she arrives to deliver a speech during a campaign meeting in Ennemain as the race enter its final stretch. Photo: Reuters, AFP

Pollsters said Macron had been boosted by his performance in a rancorous final televised debate between the two contenders on Wednesday, which the centrist was judged by French viewers to have won, according to two surveys.

Macron's strong showing in the debate, and another poll this week showing his En Marche! (Onwards!) movement likely to emerge as the biggest party in June legislative elections, have lifted the mood among investors worried about the upheaval a Le Pen victory could cause.

Le Pen was booed by several dozen protesters, including some holding Macron posters, as she visited the cathedral in Reims, northern France, where French kings were crowned in the Middle Ages.

Paris's police chief called emergency talks on security before the election after Greenpeace activists scaled the Eiffel Tower yesterday and unfurled a political banner.

Separately, police arrested a man suspected of having radical Islamist beliefs near an air base at Evreux, western France, during the night after spotting a suspicious vehicle, police and judicial sources said. Counter-terrorism prosecutors were investigating.

Security is a key election issue after attacks by militant Islamists killed more than 230 people in the past two years.

Macron was already looking ahead to being in power, telling RTL radio he had decided who would be his prime minister if he wins. He did not reveal a name, saying he would only announce the make-up of his government after he took office.

The anti-immigration, anti-EU Le Pen was not giving up.

"My goal is to win this presidential election," she said on RTL radio. "I think that we can win."

A poll on Friday showed French voters to be among the most polarised in the European Union, with one in five describing themselves as "extreme" and only about a third as "centrist".

The survey from the Bertelsmann Foundation also showed an unusually high level of dissatisfaction in France with the direction of the country, underscoring the challenge that a new president will face.