Boris Johnson has described the planned European Super League as a “kind of cartel”.
At a Downing Street news briefing on Tuesday, the prime minister said: “How can it be right to have a situation in which you create a kind of cartel that stops clubs competing against each other, playing against each other properly, with all the hope and excitement that gives to the fans up and down the country?
“Football was invented in this country, these clubs, these names, originate from famous towns and cities in our country.
“I don’t think it right that they should be somehow dislocated from their hometowns and home cities and turned into international brands and commodities without any reference to the fans who have loved them all their lives,” he said.
Mr Johnson said he believes the proposals “offend against the basic principles of competition”.
Repeating earlier comments, he added: “We want to back the FA and back the Premier League, so we can thwart this proposal before it goes much further.”
He again refused to rule out “legislative action”, but did not elaborate on what that might be.
Liverpool, Manchester United, Manchester City, Arsenal, Chelsea and Tottenham are among the 12 founding clubs of the breakaway competition.
It has received a vehement backlash, with players, pundits, Premier League clubs and politicians saying the plans are motivated solely by greed.
Earlier today the PM said “no action is off the table” and the government is “exploring every possibility” to try to block the new competition.
Similarly the Premier League says it is “considering all actions available to prevent it from progressing”.
Fourteen top clubs that are not involved in the plans say they “unanimously and vigorously rejected” them.
Questions have been raised over the power of government to intervene in the matter.
But Downing Street has not ruled out stopping players of the clubs involved getting work visas or withdrawing police funding for match days.
It has also suggested it may try to recruit the help of ministers in Spain and Italy to help coordinate efforts.
Separately, regulator the Competition and Markets Authority (CMA) has said it will be “carefully considering” the league from a competition perspective.
But earlier a Spanish commercial court in Madrid said that FIFA nor UEFA should impose sanctions on any clubs or players until the matter has been dealt with properly.