France midfielder N'Golo Kante has been ruled out for three months following an injury setback and will miss the World Cup in Qatar, sources have told ESPN.

The Chelsea midfielder is suffering from a serious hamstring injury, and the news is a significant blow for France manager Didier Deschamps given the role the 31-year-old played in his country's 2018 World Cup triumph.

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Kante's absence is also bad news for Chelsea boss Graham Potter, whose side will be without the midfielder until mid-January, sources have said.

Kante has already missed most of the season after being substituted because of injury 84 minutes into his side's 2-2 draw with Tottenham Hotspur in August.

In a news conference earlier on Friday, Potter said Kante was due to see a consultant this weekend after his latest setback.

"It's a setback so it's not good news, but anything other than that at this stage, I can't give you anything more," Potter said.

"Historically, there are things which have happened which is a concern, so we need to get to the bottom of that.

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"It's a setback at this stage of this rehab, which is worrying, but all we can do is get the right diagnosis, get the right consultation and try and help him get back to full fitness and enjoying his football."

Kante has played 262 times for Chelsea since signing from Leicester City in 2016 but has been injured for large spells during his time in west London.

Deschamps is also sweating over the fitness of Juventus midfielder Paul Pogba, who is slowly recovering from knee surgery.

That means France could start their World Cup defence against Australia on Nov. 21 without two key midfielders who helped them win the tournament four years ago.