"There is no evidence so to speak to support his proposal," said Gold, whose West Ham squad features 16 non-homegrown players. "We are very supportive of English football. We want it to be successful. But we don't want to be doing things that isn't going to work." The FA leadership can't even rely on Southgate for support, despite less than a third of the players featuring in the Premier League before the international break being English.

"Most of the data I have seen suggests quotas on squads would not make a difference because you could still field a team outside the base of British players," Southgate said.

Lawyers have questioned the merits of the FA's quotas proposal.

"(It) is completely at odds with the rest of the immigration system which requires employers to only sponsor workers at certain salary levels and to have academic qualifications or skills," said Andrew Osborne, head of immigration at London-based law firm Lewis Silkin. "Non-football employers do not have freedom to recruit who they want subject to a numerical limit."

Premier League clubs, like European counterparts, are currently allowed to transfer 16- and 17-year-old players between countries in the region under an exemption from FIFA regulations. But after Brexit, British clubs will only be allowed to sign foreign players over the age of 18, like the rest of the world. Manchester United, a record 20-time English champion, fears European rivals will be handed a competitive advantage.

"If you have 16-year-olds going to play for them and if we have to wait until 18 there are clearly practical issues there," United chief financial officer Cliff Baty has said.

Premier League executive chairman Richard Scudamore endorsed the campaign to remain in the EU ahead of the 2016 referendum. That reflected the competition's focus is maintaining the allure to domestic fans and the global television audience, with broadcast rights generating more than $3 billion per season.

"Access to talented footballers from across Europe has played a key part in the growth of the Premier League, with match attendance and global interest increasing significantly as high quality foreign players have taken their place in the competition with and against the best British and Irish players," the league said.

The government, which wants to end preferential immigration access for workers from the EU, uses the power of the Premier League to project soft power and promote British culture internationally.

"We have held positive discussions with government about the importance of access to European players for our clubs," the league said, "and the many cultural and economic benefits a globally popular Premier League brings to the UK."

Associated Press