The Premier League has issued a statement condemning the proposed breakaway European Super League, while they have been joined by Europe's major leagues to say any clubs who make the jump would be banned from domestic competition.
It was reported by The Times that five Premier League sides - Manchester United, Liverpool, Arsenal, Chelsea and Tottenham Hotspur - had agreed to join the breakaway league.
It was reported later on Sunday that Manchester City had added their name to the list to join the proposed European league.
Chelsea beat Arsenal in first Mind series friendly as fans return to Emirates
- Neville: Man Utd, Liverpool and Arsenal should be relegated over Super League plans
- Opinion: The European Super League isn't the end of football, it's more of the same
The proposal is a huge challenge to the UEFA Champions League, while it could also undermine domestic competitions, and the Premier League has issued a response warning teams against making the leap.
“The Premier League condemns any proposal that attacks the principles of open competition and sporting merit which are at the heart of the domestic and European football pyramid,” the statement read.
“Fans of any club in England and across Europe can currently dream that their team may climb to the top and play against the best. We believe that the concept of a European Super League would destroy that dream.
“The Premier League is proud to run a competitive and compelling football competition that has made it the most widely watched league in the world. Our success has enabled us to make an unrivalled financial contribution to the domestic football pyramid.
English Football Supporters' Association 'totally opposed' to Super League
“A European Super League will undermine the appeal of the whole game, and have a deeply damaging impact on the immediate and future prospects of the Premier League and its member clubs, and all those in football who rely on the funding and solidarity to prosper.
“We will work with fans, the FA, EFL, PFA and LMA, as well as other stakeholders, at home and abroad, to defend the integrity and future prospects of English football in the best interests of the game.”
The Premier League announcement was swiftly followed by a joint statement from the major European leagues, with Tancredi Palmeri reporting that any clubs who join the proposed league would be expelled from domestic competition.
UEFA said they were united with all their member associations "to stop this cynical project".
A statement was expected from the 12 clubs involved in the proposals at 21:30 BST – but their social media feeds were awkwardly quiet amid the sweeping backlash.
British Prime Minister Boris Johnson added his voice to those critical of the plans for a breakaway European Super League.
"The clubs involved must answer to their fans and the wider footballing community before taking any further steps," Johnson tweeted, adding, "we support football authorities in taking action."
The European Club Association held a meeting on Sunday, and issued a statement saying it is strongly opposed to the proposals.
Bayern boss Nagelsmann 'confident' over new Goretzka contract
United optimistic over Haaland signing - reports