The trial will begin in the next months in Paris although a date has yet to be set, said the source, who asked not to be named. Sarkozy, 64, is not the first ex-president to be prosecuted – his predecessor Jacques Chirac was given a two-year suspended sentence in 2011 for embezzlement and misuse of public funds during his time as mayor of Paris.

But it is the first time in the history of modern France that a former leader will face explicit corruption charges in court.

The influence-peddling case centres on phone conversations between Herzog and Azibert that were wiretapped by investigators looking into claims that Sarkozy accepted illicit payments from the L’Oreal heiress Liliane Bettencourt for his 2007 presidential campaign.

They suspect Sarkozy and his lawyer were seeking information on developments in the case, with Sarkozy offering Azibert a plum job in Monaco in exchange.

The inquiry also revealed that Sarkozy and Herzog often communicated via mobile phones obtained under false identities – with Sarkozy using the name Paul Bismuth.

He was cleared over the Bettencourt allegations in 2013, and has argued he should not face trial because Azibert never got the Monaco job.

But investigators believe the deal fell through because Sarkozy and his lawyer learned their phones were tapped.

Sarkozy’s defence lawyers, basing their arguments on a European Court of Human Rights (ECHR) ruling, have argued that such wiretapped transcriptions can be used only against lawyers and not their clients.

“It will be up to the court now to say if a French institution can free itself of a decision by the ECHR,” Sarkozy’s lawyer Jacqueline Laffont said.

Sarkozy, who lost the presidency in 2012 elections to his socialist rival Francois Hollande after serving just one term, has seen his post-Elysee life over the last years disturbed by a litany of legal problems.

In 2014, Sarkozy became the first former French president to be taken into police custody during a preliminary stage of the inquiry.

Last month, a top court rejected an appeal to avoid another trial, involving charges of illicit financing for the 2012 campaign.

Prosecutors claim Sarkozy spent nearly €43 million (US$48 million) on his lavish re-election bid – almost double the legal limit of €22.5 million – using fake invoices.

He has denounced the charges, saying he was unaware of the fraud by executives at the public relations firm Bygmalion, who are among 13 people also likely to face trial.

Sarkozy has also been charged over accusations he accepted millions of euros from the late Libyan dictator Moamer Kadhafi towards his first presidential campaign in 2007.

A Franco-Lebanese businessman, Ziad Takieddine, claims he delivered three suitcases containing €5 million (US$6 million) in 2006 and 2007 to Sarkozy, who was interior minister at the time, and his chief of staff.

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Meanwhile, Sarkozy’s right-wing Republicans party has also been plagued by problems, coming a lacklustre fourth in EU elections.

Some party members still see Sarkozy as their political saviour but he has ruled out a comeback.

Sarkozy begin his presidency in 2007 in a blaze of energy and publicity but found his mandate shadowed by the 2008 financial crisis.

By the end of his term, he had some of the lowest popularity ratings of any previous post-war French leader.

After his humiliating 2012 defeat, Sarkozy famously promised that “you won’t hear about me any more”, a prophecy that has turned out to be anything but true.