Gianni Infantino has been in charge of Fifa for 10 years. Uefa has threatened legal action over Gianni Infantino's scrapped plans to sell off stakes in Fifa competitions to private investors. The English Football Association is also set to write to Infantino withdrawing its previous support.

Infantino's leadership had already been publicly questioned by football's governing bodies in Europe, North and Central America and the Caribbean, with Uefa and Concacaf releasing statements criticising the plans.

And on Monday, Wales became the first nation to publicly withdraw backing for Infantino's bid to continue as Fifa president. Fifa and Infantino wanted to create a commercial subsidiary to run its main events, including its World Cups, and external investors would have been able to buy stakes in it.

World football's governing body said it would "invite third parties to make minority, non-controlling investments" in a new subsidiary called Fifa Forward Enterprise (FFE). As first reported by The Telegraph, Uefa said in a letter to Infantino "it is actively considering legal action, arbitration, and/or regulatory complaints (together, the 'proceedings') arising out of and in connection with the FFE plan proposed by Fifa".

Uefa added it wants "immediate steps to identify, locate and preserve all documents and electronically stored information described in this notice that are in your or Fifa possession, custody or control. "These obligations arise independently of any internal retention policy you or your organisation maintain and supersede any routine document destruction or deletion policies that would otherwise apply."

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Infantino wrote to all 211 Fifa member associations saying they would receive $40m (£30m) if they backed his controversial proposal, setting a deadline of 19 September if they wanted to access an initial $20m (£15m).

Thrive Eternal was expected to lead the proposed investor group for FFE. Thrive is an American venture capital firm founded by Joshua Kushner - the brother of US President Donald Trump's son-in-law Jared.

Uefa's request for all documents regarding the investment plan included "email, instant messages (WhatsApp, Signal, Teams, Slack or any other platform), SMS, written correspondence and meeting notes", and those which involved "any Fifa officer, employee, committee member, consultant or agent, or any Fifa member association, confederation, broadcaster, sponsor, or financial institution".

In reference to the 19 September deadline, Uefa added it wanted documents to be retained "relating to the payment structure for Fifa member associations, including the design, modelling, legal basis, approval and communications to member associations".

Uefa asked Infantino to acknowledge receipt of its letter in writing within five business days, to confirm he had "received and understood this notice" and that he has "taken immediate steps to preserve relevant materials as required". This heaps yet more pressure on the beleaguered Fifa president Gianni Infantino, and is further evidence that the revolt against him over the FFE saga is being driven by Uefa.

The demand that senior Fifa officials do not destroy any evidence relevant to the scrapped plans to sell off stakes in its competitions will be uncomfortable for those named in the letter, and represents a further escalation in the feud between the two organisations.

It remains uncertain whether the threat of legal action - and European member associations withdrawing previous letters of support - is enough for Infantino to consider his position and step down.

But, if not, Uefa will hope it at least helps to secure the 19 votes needed (of 37) to force an emergency meeting of the Fifa Council at which Infantino could face a demand to step down.

A motion to call one will not be submitted until they are certain they have the required numbers, but that could be where this dramatic story is heading next.

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