Infantino's secretive proposal to raise $US4.2 billion ($A6bn) from investors including the New York investment firm of Joshua Kushner - brother of US President Donald Trump's son-in-law Jared Kushner - was dropped on Saturday, days after the revelation in media reports provoked a global furore.
UEFA led the backlash and on Thursday its 55 member federations agreed to boycott all FIFA events and competitions while the proposal was active.
Now lawyers for UEFA have informed FIFA that the European body is "actively considering legal action, arbitration, and/or regulatory complaints ... arising out of and in connection with the FFE (FIFA Forward Enterprise) plan proposed by FIFA and all related matters".
The letter, seen on Monday by The Associated Press, named 18 FIFA executives who it said should retain data, documents and electronic messages as potential evidence. Besides Infantino they include former Arsenal manager Arsene Wenger, now FIFA's head of global soccer development.
UEFA have signalled it wants to end Infantino's decade-long presidency, saying he had lost the confidence of world football. The Swedish soccer federation confirmed on Monday that UEFA is actively looking "to come up with an alternative candidate" as FIFA president. The next election is scheduled in March.
Infantino withdrew the divisive proposal that offered FIFA's 211 member federations one-off payments of $US20 million ($A29m) each with a mid-September deadline to accept.
The FFE spin-off valued by FIFA at $US20 billion ($A29bn) would have taken control of the football body's money-making commercial and tournament operations. The 211 members, who were offered one-off payments of $US20 million ($A29m) each with a mid-September deadline to accept, currently own the Zurich-based not-for-profit governing body.
Legal proceedings are "reasonably anticipated," UEFA's lawyer Andrew J Levander wrote, citing the belief of the sport's stakeholders that the plan was "fundamentally incompatible with the proper governance of football".
The English FA is understood to be writing to FIFA making it clear Infantino no longer has its support, while the Football Association of Wales became the first country to publicly withdraw support for the Swiss.
UEFA has been most outspoken against its former employee Infantino while the Asian Football Confederation and CONCACAF, the North and Central American and Caribbean football body, also have made strong statements opposing Infantino's plan.
Infantino has most support from his traditional base in Africa, while South America's CONMEBOL wants him to expand the 2030 World Cup to 64 teams from 48.
The private equity plan has provoked a stunning turnaround in fortunes for Infantino who left New York after the World Cup final two weeks ago seemingly a lock to be re-elected unopposed for a fourth and final term in office through 2031.
The New York Post reported Infantino had repeatedly tried and failed to reach President Trump by phone since the proposal collapsed, and that the FIFA chief felt "isolated" by an avalanche of negative media coverage.
The Post also reported that Infantino had scheduled private talks with Secretary of State Marco Rubio. However, the US Assistant Secretary of State for Global Public Affairs Dylan Johnson said in a post on X that there were "no plans" for Rubio to speak with 56-year-old Swiss-Italian.
with agencies
