France's highest court has upheld a sentence against former French President Nicolas Sarkozy over the illegal financing of his 2012 re-election campaign.

He was found guilty of overspending on his campaign, then hiring a PR firm named Bygmalion to cover it up.

In 2024, Sarkozy, 70, was handed a one-year sentence of which six months were suspended, meaning they could be served by wearing an electronic tag instead of going to jail.

He has always denied all allegations.

Prosecutors in the case said Sarkozy's UMP party spent nearly double the €22.5m (£19.4m) cap on his campaign, splurging on lavish campaign rallies and events.

To hide the costs, UMP then asked Bygmalion to invoice the party, rather than the campaign.

Today's ruling marks the former president's second definitive conviction, having been in power from 2007 to 2012.

Last December, the High Court of Appeal upheld a corruption conviction, forcing Sarkozy to wear an electronic monitoring bracelet for six months.

Then, in September, he was sentenced to five years in jail after being found guilty of criminal conspiracy. He spent 20 days in jail before being released earlier in November.

An appeal trial will be held next year. Until then, Sarkozy will be subject to strict judicial supervision and barred from leaving France.

In the days following his release, Sarkozy announced he was writing a book about his three weeks in jail, titled A Prisoner's Diary. An excerpt published on social media reveals his reflections on the prison experience.