Twelve of Europe's biggest clubs are reported to have agreed to take part in the controversial breakaway competition, with six from England's Premier League said to have given it the thumbs-up.

The news emerged a day ahead of UEFA's executive committee meeting, at which plans for future 36-team Champions League competitions were expected to be confirmed by European football's governing body.

UEFA issued a statement in conjunction with major domestic bodies such as the Football Association (FA) and the Premier League, and their Italian and Spanish counterparts.

The FA also issued its own firm rejection of the Super League concept, saying any closed-shop competition would go against the sacrosanct, long-standing principles of the game.

Aware of "certain English clubs" joining the project, the FA said: "It is clear that this would be damaging to English and European football at all levels and will attack the principles of open competition and sporting merit which are fundamental to competitive sport.

"For new competitions to be formed involving clubs from different associations, approval would be required from the relevant national associations, confederation and/or FIFA. We would not provide permission to any competition that would be damaging to English football, and will take any legal and/or regulatory action necessary to protect the broader interests of the game.

"We note FIFA confirmed earlier this year that they and the six confederations would not recognise any such competition and, as such, any player or club involved may not be permitted to participate in any official competition which falls within the auspices of FIFA or their respective confederation."

It was reported that confirmation of the new league being launched could come as soon as Monday (AEST) in Europe.

The FA said it would "continue to work with UEFA, FIFA and the Premier League to seek to ensure that nothing is approved that has the potential to damage English football".

It added that it would also work with the players' and managers' unions - the PFA and LMA - along with the English Football League and Premier League, motivated by the objective "to defend the integrity and future prospects of English football in the best interests of the game".

The UK Government's culture secretary Oliver Dowden said clubs signing up for any such project would be neglecting their duty to supporters by taking away their say.

"Football supporters are the heartbeat of our national sport and any major decisions made should have their backing," Dowden said.

"With many fans, we are concerned that this plan could create a closed shop at the very top of our national game. Sustainability, integrity and fair competition are absolutely paramount and anything that undermines this is deeply troubling and damaging for football.

"We have a football pyramid where funds from the globally successful Premier League flow down the leagues and into local communities. I would be bitterly disappointed to see any action that destroys that."