Former French president Nicolas Sarkozy was sentenced to five years in jail on Thursday after being found guilty of criminal conspiracy over efforts by close aides to procure funds for his 2007 presidential bid from Libya during the rule of late dictator Muammar Gaddafi.

Sarkozy was acquitted by a Paris court of all other charges, including corruption and receiving illegal campaign financing.

But the ruling means the former president will spend time in jail even if he appeals, a sentence much harsher than many expected.

Sarkozy, who has always denied the charges, was accused of making a deal with Gaddafi in 2005, when he was France's interior minister, to obtain campaign financing in exchange for supporting the then-isolated Libyan government on the international stage.

The judge said there was no proof that Sarkozy made such a deal with Gaddafi, nor that money that was sent from Libya reached Sarkozy's campaign coffers, even if the timing was "compatible" and the paths the money went through were "very opaque".

But she said Sarkozy was guilty of criminal conspiracy for having let close aides get in touch with people in Libya to try and obtain campaign financing.

The 70-year-old has been on trial since January, in a case he said was politically motivated.

The court found him guilty of criminal conspiracy between 2005 and 2007. After that he was president and covered by presidential immunity, the court added.

Among the other accused in the trial were Sarkozy's former right-hand man Claude Gueant and former Interior Minister Brice Hortefeux. The court found Gueant, also a former Interior Minister, guilty of corruption, among other charges. Hortefeux was found guilty of criminal conspiracy.

Despite his legal battles, and having his Legion of Honour, France's highest distinction, stripped in June, Sarkozy remains an influential figure on the French political stage.

He recently met with his former protege, Prime Minister Sebastien Lecornu, and has also lent credibility to the National Rally (RN), led by Marine Le Pen, saying the far-right, anti-immigrant party now forms part of the "republican arc."

Sarkozy has faced several legal battles since leaving office.

Last year, France's highest court upheld his 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.

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 next month.