The Premier League says the "uncertain nature" of the "political and regulatory landscape" means it is impossible to predict what effect the UK's decision to leave the European Union will have on English football.

On Thursday, the UK public voted 51.9 percent to 48.1 percent in favour of withdrawing from the EU, which means players from other countries within the Union might not have an automatic right to play in England once the so-called Brexit is complete.

In a statement, the league said: "The Premier League is a hugely successful sporting competition that has strong domestic and global appeal. This will continue to be the case regardless of the referendum result.

"Given the uncertain nature of what the political and regulatory landscape might be following the 'Leave' vote, there is little point second-guessing the implications until there is greater clarity.

"Clearly, we will continue to work with Government and other bodies whatever the outcome of any process."

All countries within the EU agree to the free movement of labour, which extends to players and coaches. There is no guarantee, however, that this will continue be the case in a few years when the UK has split. Arsenal's Czech goalkeeper Petr Cech shared his opinion on Twitter Friday:

.@GMB It looks like the biggest decision in the history of this country was made based on fake campaign and lies ... https://t.co/8PWLqdnqLq - Petr Cech (@PetrCech) June 24, 2016

With immigration concerns one of the major factors driving the vote to leave the EU, the UK could try to broker a trade agreement that does not include the free movement of people.

If that happens, then the 432 European players who Sky Sports reported were registered to play in the Premier League last season would need work permits.

And a study by the BBC asserted that more than 100 Premier League players, and a total of 332 players including the Championship and Scottish Premiership, would be ineligible for a work permit under the current regulations.

Cesc Fabregas joined Arsenal from Barcelona at age 16, but he may no longer be able to play for them after the Brexit. Richard Heathcote/Getty Images

Equally concerning for clubs would be the regulation governing the registration of youth players.

FIFA rules state that players under the age of 18 cannot be transferred across borders. However, players as young as 16 who transfer within the European Union are exempted from the FIFA rule due to freedom of movement of labour laws covering people from minimum working age (defined as 16).

This means 16-year-olds have always been able to move between European clubs when they reach professional-contract age, and that in turn has led to hundreds of players switching clubs for a minimal compensation fee.

Arsenal, most notably with Hector Bellerin and Cesc Fabregas, and Manchester United, with Adnan Januzaj and Timothy Fosu-Mensah, are just two examples of clubs taking young players from other European countries at 16.

If the UK's new trade agreement with the EU does not include free movement of players, it is almost certain that English clubs would not be allowed to sign these players before the age of 18. But the likes of Barcelona, Bayern Munich, Juventus and Real Madrid would be able to carry on as usual within the EU.

It would have a dramatic knock-on effect for the Elite Development Squad system within Premier League academies. While Premier League clubs would no longer be able to sign young European talent, the bright side for English players would be that many who would usually be dropped by clubs at 16 would have another two years to prove they have the ability.

Retired English player Gary Lineker has been vocal in his opposition to the Brexit, referencing the UK Independence Party, or UKIP:

U kip for a couple of hours and look what happens. What have we gone and done? - Gary Lineker (@GaryLineker) June 24, 2016

Greg Dyke, chairman of the Football Association, told Press Association Sport that it was "too early" to know the impact of leaving the EU.

"It could take two years to really know, but there could be quite an impact on English football because of Brexit," he said. "It would be a shame if some of the great European players can't come here, but I don't think that will happen. Whether the total number reduces will depend on the terms of the exit.

"My personal view has always been that the decline in the number of English players in Premier League first teams -- we're down to about 30 per cent now -- is a shame. If it increases the number of English players, that is to be welcomed. But you don't want to lose the best European players coming here."

Dyke has long campaigned to get more English players into the Premier League and has tightened up regulations to make it more difficult for non-EU players to get a work permit.

Italy defender Giorgio Chiellini has expressed his shock and regret at the result of the referendum.

"It shocked everybody this morning," he said during a news conference in Montpellier, France, where Italy are based for the European Championship. "We all went to bed last night sure that Brexit would not win and [UK] would remain in the European Union, but sadly this didn't happen.

"I believe that the biggest concern is the domino effect this decision could now provoke. What would be bad would be if other countries start thinking about doing the same, and sadly this could happen.

"I've found myself asking if there were a referendum tomorrow in Italy, how would it go? I'm not so convinced Italy has the strength to refuse to exit, just because when people are unhappy they vote for change, and this has sadly happened in the UK.

"I'm sorry that the UK is exiting the EU, regardless of what it could mean for us. Maybe little will change because if it's only UK, it won't change much, but it's horrible news."

Germany goalkeeper Manuel Neuer said: "I grew up in a time in which it was normal that the European Union was one. It is a shame that [the UK] will no longer be part of it."