A Paris appeals court on Monday decided to release former French president Nicolas Sarkozy from prison and place him under judicial supervision. Sarkozy left prison just a few hours later, less than three weeks after he began serving a five-year sentence for criminal conspiracy in a scheme to finance his successful 2007 election campaign with funds from Libya.

He was acquitted of all other charges, including corruption and receiving illegal campaign financing. Sarkozy's prison sentence was enforced immediately because of the"extraordinary seriousness" of the crime, judge Nathalie Gavarino told the court.

Sarkozy will be banned from leaving the French territory, the court said. An appeal trial is expected to take place later.

Former French president Nicolas Sarkozy awaits court rulling on early release

French prosecutors had requested Sarkozy's release under judicial supervision.

"The risks of collusion and pressure on witnesses justify the request for release under judicial supervision," prosecutor Damien Brunet said in court, asking that Sarkozy's request for release be granted.

'Gruelling' ordeal

Sarkozy, 70, became the first former French head of state in modern times to be sent behind bars after his conviction on September 25. He was jailed on October 21 pending appeal but immediately filed for early release.

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The former president, who governed from 2007 to 2012, denies wrongdoing and says he is the victim of a “plot” linked to the former Libyan leader Muammar Gaddafi.

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Sarkozy told the court via videolink that his three-week imprisonment had been "gruelling".

"It's hard, very hard, certainly for any prisoner. I would even say it's gruelling," he said, adding that he wanted to pay tribute to the prison personnel who had"made this nightmare... bearable".

Last year, France's highest court upheld a conviction for corruption and influence peddling, ordering him to wear an electronic tag for a year, a first for a former French head of state. The tag has now been removed. Sarkozy is also the subject of an ongoing investigation into alleged witness tampering in the Libya case.

Also last year, an appeals court confirmed a separate conviction for illegal campaign financing over his failed re-election bid in 2012. A final ruling from France's highest court is expected on that case this month.