The chairman of Europe's football leagues insists they are ready to defy Uefa over the governing body's "totally crazy" plans for changes to the Champions League and Europa League.
Lars-Christer Olsson said the leagues might break their agreement not to schedule domestic fixtures on the same night as Uefa competitions unless changes set to take effect from 2018 were scrapped.
If the European Professional Football Leagues (EPFL) threat were carried out, it could mean heavyweight Premier League matches competing with Champions League games for television audiences.
Olsson accused Uefa of failing to consult the EPFL on the proposals, which he said would make it harder for all but the biggest teams to compete and called "the first step towards a closed [European super] league".
"Uefa decided to break conditions in the memorandum of understanding. If we terminate [it] there is no obligation for leagues to stick to this agreement," he told the Leaders Sport Business Summit in London on Wednesday.
"In the end it would not be good for anybody, so the only sensible thing coming out of this is an agreement."
Asked if that could mean domestic matches clashing with European fixtures, he said: "Absolutely, but that has to be decided by the leagues."
Uefa president Aleksander Ceferin, who replaced the banned Michel Platini last month, has vowed to reconsider the controversial plans, which were agreed before the Slovenian's whirlwind election.
Olsson, who is set to meet Ceferin this week, said the EPFL would discuss possible action at its general assembly later this month.
The Swede accused Uefa's executive committee of being "weak" and said the ECA, which lobbies on behalf of more than 200 clubs, had been hijacked by a cabal of powerful teams.
"There has been a vacuum of leadership in Uefa and I think the big clubs have taken advantage of that," he added.
"Twenty-eight clubs in the ECA are making the decisions, not the 200 clubs, so there are some structures we have to look into. There was a vacuum at Uefa and that has led to this mess."
Olsson said the EPFL accepted that some changes to the competition formats were necessary but said the plans to guarantee four Champions League places to the top four countries and alterations to the way revenue is distributed would cement the position of the current elite.
"The Premier League is a good example where you have a proper competitive balance, any team can win the competition," he said.
"It should be a similar relationship in the top competition in Europe. The dream has to live. The smaller and medium sized clubs with ambitions have to know it is possible to play in the Champions League and make results. This is absolutely possible to combine."
He also rejected plans to create a new body, jointly run by Uefa and the ECA, to manage the Champions League and Europa League. He added: "That is totally crazy because it is the first step towards a closed league."