François Fillon faces a crisis in his campaign for the French presidency with prosecutors having opened an inquiry for misuse of public funds after a report that his wife drew a salary as his assistant but had never actually worked.
Mr Fillon, a right-wing former prime minister, said earlier he was outraged at the report by the satirical weekly Le Canard Enchaine which he said showed “contempt and misogyny”.
“I see the stink bomb season has started,” the 62-year-old said from the city of Bordeaux.
Just hours later, financial prosecutors in Paris said they were opening an inquiry into potential misuse of public funds relating to the matter.
“Following the publication on 25 January 2017 in Le Canard Enchaine of a story calling Mrs Penelope Fillon into question, the financial prosecutor'ss office today opened a preliminary investigation into misappropriation of public funds, misuse of company assets and concealment of these offences,” a statement said.
It is common practice for French parliamentarians to employ wives and children in their offices.
But the allegation that Mr Fillon's British-born wife, Penelope, was paid for fake jobs – a charge to which he did not reply directly on Wednesday – could undermine his pledge to pursue an honest and transparent campaign, and hurt his ratings as the race for the presidency gathers pace.
Mr Fillon is running for the Republican party in the presidential election on 23 April and 7 May.
While favourite to win election, he faces a strong challenge from the far-right leader Marine Le Pen, second in the polls, and from the independent centrist Emmanuel Macron.
That lead could be affected by how Mr Fillon handles a crisis that risks denting his image as a devout Catholic and family man with a relatively scandal-free record in office.
Polls have for months highlighted voter discontent with the political elite and any hint of improper use of public finances could worsen that perception at his expense.
For the French voter, the case has echoes of past scandals over “phantom” jobs.
Alain Juppe, another former prime minister whom Mr Fillon was visiting in Bordeaux on Wednesday, was convicted over use of public funds for fake jobs more than 10 years ago in a case that also led to the conviction of former President Jacques Chirac.
Socialist former prime minister Manuel Valls, who hopes to win his party's ticket as presidential candidate, urged Mr Fillon to explain himself on the matter.
“You can't be the candidate of honesty and transparency and not respond,” Mr Valls told France Inter radio.
Ms Le Pen usually trades in voter distrust of mainstream leaders but she has so far remained silent.
Her own Front National (FN) party is under judicial investigation over allegations of improper employment of assistants by its MEPs in the European Parliament.
Le Canard Enchaine reported that Penelope Fillon had been paid €600,000 (£511,000) for many years of employment as a parliamentary assistant to him and later to his replacement as a National Assembly lawmaker, and for work at a cultural journal.
It said that its research had showed there was no evidence she had ever really worked.
Mr Fillon's public relations team have emphasised there is nothing illegal about her working for her husband in the National Assembly.
They explained her apparent absence from the workplace by saying she preferred to work “in the background”, in keeping with a self-effacing style. They have not said how much she was paid.
Mr Fillon and his wife, who is from Wales, were married in 1980 and have five children. Last October, she told a newspaper, Le Bien public: “Up to now, I have never been involved in the political life of my husband.”
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