French war-right leader Marine Le Pen and centrist candidate Emmanuel Macron clashed over Europe as the presidential candidates went head-to-head in the second live TV debate.

Macron on Tuesday said Le Pen's nationalist proposals amounted to "economic warfare", BBC reported.

She was also accused by the right of not being tough enough on France's membership of the European Union. Francois Fillon said that France needed Europe when up against the US and China.

Le Pen, leader of the National Front (FN) party, promised to restore control of France's borders and scrap the euro, or else hold a referendum on EU membership.

Speaking alongside 10 other candidates as things got a little heated in the second of three televised French presidential election debates, Le Pen said her presidency would improve the lives of French citizens.

Macron, the frontrunner, accused Le Pen of lying, and said that "nationalism is war".

"You are saying the same lies that we've heard from your father for 40 years," he said.

Le Pen, who also came under attack from conservative candidate Fillon, retorted: "You shouldn't pretend to be something new when you are speaking like fossils that are at least 50 years old."

Meanwhile, nationalist right-wing outsider Francois Asselineau said he was "the only true candidate of Frexit", and promised to trigger Article 50 -- the process to start the country's divorce from the EU -- immediately if he were to win power.

The debate was extended to include the six minor candidates, so inevitably it is on them that water-cooler conversation is going to focus.

On Jean Lasalle -- "son of a shepherd, brother of a shepherd" -- with his impenetrable Pyrenean accent; on Francois Asselineau with his "Frexit" obsession; on the rival Trotskyites Philippe Poutou and Nathalie Arthaud with their rousing calls to punish the bosses.

According to the BBC, after a while there were really only two people -- Francois Fillon and Emmanuel Macron -- defending the way things are.

Everyone else -- from Marine Le Pen to the uber-Gaullist Nicolas Dupont Aignan to the firebrand of the left Jean-Luc Melenchon (as brilliant as ever on stage) -- wants the rules of Europe and the economy totally rewritten.

Turning the topic to security, Le Pen said that France had become a "university for jihadists", prompting angry interruptions from the left-wing candidates.

Most polls suggest that Le Pen and Macron will face each other in the two-candidate run-off for presidency on May 7.

However, Tuesday's debate gave Fillon, 63, an opportunity to close the gap on the leaders.

Fillon was the frontrunner in the campaign until he was hit by the "fake jobs" scandal and placed under formal investigation.

He is accused of paying hundreds of thousands of euros to his family for work they did not do.

He was trailing third in the first round, according to polls, a position which would eliminate him from the race.