PARIS (Reuters) - A new poll on Tuesday showed far-left wildcard Jean-Luc Melenchon nipping at the heels of the frontrunners in France's presidential race, building on his recent surge as sniping between the top contenders gathered pace.
With just 12 days to go until the first round of voting, polls are tightening and possibilities for May's second, deciding round, tipped for weeks to be between far-right leader Marine Le Pen and centrist Emmanuel Macron, are opening up.
Conservative candidate Francois Fillon stepped up his attacks against Macron, with whom he is in competition for centre-right voters, calling him a liar. Macron responded, on Sud Radio: "Mr Fillon is a man of little worth."
Meanwhile Melenchon's support jumped seven percentage points to 19 percent in a monthly Ifop-Fiducial poll for Paris March and Sud Radio, putting him in third place ahead of Fillon.
He is also targeting Macron's voters -- but this time those to the left or centre-left.
Melenchon and Fillon, on 19 percent and 18.5 percent, respectively, still lag Le Pen on 24 percent and Macron on 23 percent. But the two frontrunners are losing steam.
Macron is widely expected to win against Le Pen if both progress to the second round. The poll also showed some 32 percent of voters could abstain in the first round on April 23.
Melenchon's rise in polls, the latest episode in an election campaign full of surprises, has unnerved financial markets and prompted a warning on Tuesday by the head of business lobby group Medef Pierre Gattaz.
Calling both Melenchon's and Le Pen's programmes "an absolute catastrophe" for France, Gattaz warned on Europe 1 radio against a possible Melenchon-Le Pen second round.
"That Le Pen-Melenchon second round shouldn't take place," he said.
Though Melenchon is on the polar opposite of the political spectrum from Le Pen, in particular on immigration, they both distrust the European Union, want to renegotiate France's role in it and hold a referendum on EU membership.
The turbulent presidential campaign has become increasingly bitter in recent weeks as candidates eye the finish line.
Fillon has been under fire since January over allegations his wife was paid hundreds of thousands of euros for minimal work as a parliamentary assistant for several years. The couple are formally being investigated by magistrates.
He again accused the Socialist led-government of helping to spread the allegations on Tuesday.
A daily Opinionway poll showed Macron winning the second round against Le Pen, with Melenchon in fourth place right behind Fillon in the first round.
(Reporting by Sarah White, Sophie Louet and Helene Dauschy; Editing by Ingrid Melander/Jeremy Gaunt)