Manchester United bidder Sir Jim Ratcliffe could be forced to sell his stake in French club Nice to avoid the prospect of one of his teams being excluded from the Champions League if he wins the race to buy out the Glazer family and take ownership of the Premier League side, a source has told ESPN.

Ratcliffe, a boyhood United fan and Britain's richest man with a reported fortune of £6.1 billion, has lodged a bid with the New York bank Raine Group to buy the Glazers' 69% stake in United. If Ratcliffe is successful, he and his chemicals company INEOS would be the owners of three clubs -- United, Nice and Swiss second tier side FC Lausanne-Sport.

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And although UEFA president Aleksander Ceferin said earlier this month that European football's governing body was ready to review regulations around multi-club ownership, Ratcliffe would contravene existing rules if both United and Nice qualified for the same UEFA competition under his ownership.

Article 5 of UEFA's club competition regulations relates to integrity of the competition and multi-club ownership, with the rules forbidding two teams controlled by the same person or group from competing in the same competition.

In 2017, a UEFA panel of financial experts accepted that the Red Bull group had sufficiently restructured and separated the management structure of RB Leipzig and Red Bull Salzburg -- known as FC Salzburg in UEFA competition -- to enable both the German and Austrian teams to participate in the Champions League together.

But unless Ratcliffe and INEOS diluted their interest in Nice, they would risk the French side or United falling foul of Article 5.02 of UEFA regulations which outlines the steps that would be taken if two clubs owned by the same person or group qualified for the same competition.

If both teams finished in the Champions League qualification spots in their respective leagues, the club finishing higher would take the place in the competition, meaning that United would miss out if they finished fourth and Nice finished in Ligue 1's top three.

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The clause states that, "If two or more clubs fail to meet the criteria aimed at ensuring the integrity of the competition, only one of them may be admitted to a UEFA club competition, in accordance with the following criteria (applicable in descending order):

"The club which qualifies on sporting merit for the most prestigious UEFA club competition [i.e., in descending order: UEFA Champions League, UEFA Europa League or UEFA Europa Conference League]; The club which was ranked highest in the domestic championship giving access to the relevant UEFA club competition; The club whose association is ranked highest in the access list [see Annex A]."

Sheikh Jassim bin Hamad Al-Thani, who is leading the Qatari bid to buy United, may also be forced to prove that he has no influence in the running of Paris Saint-Germain, which are owned by Qatar Sports Investments (QSI), should he become United's owner.

But as the owner of Nice, Ratcliffe's influence would automatically come under UEFA scrutiny should he emerge as the successful bidder in the race to buy United.