Uefa is planning an independent review of Fifa’s abandoned proposal to sell a stake in the commercial rights to the World Cup after raising concerns the tournament may have been undervalued, according to the Guardian.

The proposal, known as the Fifa Forward Enterprise plan, would have seen a 21 percent stake sold to US private equity firm Thrive Capital for $4.2 billion. The deal valued Fifa’s commercial assets at about $20 billion.

According to the Guardian, Uefa wants to understand how that valuation was reached and whether a competitive bidding process took place.

“We need to find out if they were selling the World Cup at a knockdown price. How did they get to $20bn? Was it a robust process?” a source familiar with Uefa’s plans told the newspaper.

The proposal was withdrawn last week after all 55 Uefa member associations threatened to boycott the World Cup and other Fifa competitions.

The Guardian reported that Uefa is also continuing its campaign to remove Fifa president Gianni Infantino despite his written apology to Fifa’s 211 member associations following crisis talks in Morocco.

Market analysts cited by the newspaper questioned whether the $20 billion valuation reflected the true value of the World Cup, with one source saying: “The World Cup is the only genuinely global mass entertainment event so an increase of $5bn on current revenues seems low to me.”

Fifa said on Wednesday that Infantino retains the organisation’s “full support”.