France can expect an “enormous double surprise” on Sunday night when voters eliminate Nicolas Sarkozy, the favourite for the presidency, and send Jean-Marie Le Pen, the National Front leader, into the May 6 run-off.

Mr Le Pen’s blue eyes twinkled with the old menace when he made that forecast yesterday to The Times and other foreign media. Such predictions from the far-right bogeyman used to produce laughs but since 2002, when he reached the run-off against President Chirac, he is not a joke.

Ending his fifth and probably last campaign for the presidency, Mr Le Pen, 78, was in expansive mood as he offered his usual sulphurous cocktail of xenophobia and nostalgia, laced this time with a sense of vindication. The old pariah has become more of a wicked uncle now that his themes have been borrowed by Mr Sarkozy, 52, the conservative front-runner, and to a lesser extent Ségolène Royal, 53, the Socialist.

To woo the 15-20 per cent of voters who sympathise with Mr Le Pen’s ideas, Mr Sarkozy has swung hard right, borrowing his rhetoric on immigration, law and order and French identity. Ms Royal has followed mildly, upsetting the traditional Left with calls for Tricolours in every household and singing the Marseillaise at her rallies.

“They have all moved right except me,” Mr Le Pen joked. His highest esteem is for Mr Sarkozy in what is seen as a tactic intended to discredit the favourite by contaminating him with praise. “I have no quarrel with Sarkozy and he has been the picture of courtesy with me. We are like two boxers in a match, not enemies,” Mr Le Pen said. He was flattered that Mr Sarkozy had taken his ideas over immigration but the French would “prefer the original to the copy”, he said.

He opened another line of attack against Mr Sarkozy this week, bringing up rumours that have swept the internet on the absence from the campaign of Cécilia Sarkozy, the candidate’s wife. Mr Le Pen accused the media of cowardice in not publishing rumours that say that Mrs Sarkozy, who returned last year after a highly publicised relationship with another man, had left the family home again.

Mr Le Pen also predicted yesterday that Ms Royal, 53, will be eliminated on Sunday because she had bungled her campaign and would be “crucified” by voters abandoning her for the fringe candidates of the far Left.

Such talk is usually dismissed as bluster but Mr Le Pen recalls that he was alone in predicting as far back as 2002 that Ms Royal, then a minor figure, would become Socialist candidate in 2007.

No experts give credence to the idea of a run-off between Mr Le Pen and François Bayrou, 55, the centrist who has threatened to force out Ms Royal. A batch of polls yesterday showed the two front-runners still ahead, but with one third of voters still undecided. This uncertainty is unnerving the Sarkozy and Royal camps and feeding the hopes of Mr Bayrou and the National Front leader.

For the far-right champion, Mr Sarkozy is not qualified to run because he is not really French. Mr Le Pen, who was a paratroop officer in the colonial wars in Algeria and Vietnam, has scored headlines over the past week with this new theme, based on Mr Sarkozy’s origins as the son of a Hungarian immigrant and grandson of a Greek Jew on his mother’s side.

“The head of state is the incarnation of the nation and the French people,” Mr Le Pen said yesterday. “It seems that Sarkozy has only one grandparent of French origin. It is quite legal for him to become president but not ethical,” said the 100 per cent Breton politician.

Mr Le Pen, who was fined in 1987 for calling the Nazi death camps “a detail of history”, said that he saw no reason why Iran should not have nuclear weapons, since Israel already had them and Tehran would be “incinerated” if it tried to attack anyone. He also told an Israeli newspaper that French Jews should vote for him. “Jews who are French and linked to France, and whose interests are those of France, should vote for me as a bloc,” he said.

Polls give Mr Le Pen about 14 per cent of Sunday’s vote. Mr Sarkozy and Ms Royal are in the high 20s with Mr Bayrou at least five points below them.

Read Charles Bremner on the French elections

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