The ECB has warned the 18 first-class counties that Kolpak cricketers will no longer be eligible to play here domestically beyond the end of the 2020 season if the UK completes a no-deal Brexit deal this year.

And that any sort of Brexit before the end of next year will effectively spell the same thing.

The governing body has circulated an email listing likely scenarios for players currently qualified to participate here as locals by virtue of a Kolpak registration or the holding of an EU passport.

Duanne Olivier (pictured) is one of the players who would be affected by a no-deal Brexit

WHAT IS A KOLPAK DEAL? Ruling was created by the European Court of Justice in 2003 after Slovakian handball player Maros Kolpak initially lost his contract at a German club as they already had two non-EU players. Court ruled in his favour and allowed citizens of countries that had fair trade treaties with the EU, to work in any EU country. Ruling allows citizens of around 100 nations to play cricket in any EU nation without being considered an overseas player. South African Claude Henderson became the first cricketer to sign a Kolpak agreement, joining Leicestershire in 2004. Advertisement

In the event of a no-deal departure from the EU either on October 31 or the proceeding two months, it has been advised that new applications for the registration of Kolpak/EU cricketers under regulation 2 of the ECB's protocols would become void with immediate effect.

Under the proposals, those already contracted here will be permitted to continue under their existing terms for 2020 - provided they remain at their current clubs - but it has been advised that any amnesty must end in conjunction with the government's Brexit transition period on December 31, 2020.

New applications would still be processed in the event of a deal being struck with the EU any time up to the end of 2020 but the 40-or-so county cricketers affected by the directives would still not be eligible to play as locals in 2021. At that point, existing deals would be cancelled and only those switching to overseas player terms could continue in competitions like the County Championship and Twenty20 Blast.

It is understood that the highest-profile of a raft of recent Kolpak recruits, the fast bowler Duanne Olivier - who sensationally revealed to Sportsmail earlier this year that he wanted to pursue a Test career with England after turning his back on South Africa - has a clause in his three-year contract with Yorkshire that would trigger an immediate switch to overseas status if and when Brexit dictates.

Morne Morkel is another Kolpak player who would be unable to play in event of no-deal Brexit

KOLPAK CRICKETERS IN LAST THREE YEARS 2019: Duanne Olivier (Yorkshire) 2018: Wayne Parnell (Worcestershire), Blessing Muzarabani (Northamptonshire), Morne Morkel (Surrey), Heino Kuhn (Kent) 2017: Shivnarine Chanderpaul (Lancashire), Marchant de Lange (Glamorgan), Rilee Rossouw (Hampshire), Kyle Abbott (Hampshire), Grant Elliott (Warwickshire), Daryn Smit (Derbyshire), David Wiese (Sussex), Tino Best (Hampshire) Advertisement

Dual national players who hold British passports will continue to be eligible for registration regardless but the future for Kolpaks, plus those with EU passports or ancestry visas, looks bleak.

The ECB are known to have taken legal advice before issuing their correspondence while the Professional Cricketers' Association have in turn offered their members the chance to speak to a lawyer.

Kolpak players - hailing from southern Africa and the Caribbean - first arrived here in 2004, the year after handball goalkeeper Maros Kolpak made a successful challenge to the European Court of Justice to allow him to continue playing in Germany as a local due to a trade agreement his native Slovakia held with the EU.

Claude Henderson, a spinner with seven Test caps, was cricket's pioneer with Leicestershire, using Kolpak's same argument and the terms of the Cotonou Agreement - a trade deal signed between the EU and 78 countries, including South Africa, that advocated the same rights to their citizens as their European equivalents.

The initial flood of signings in the Noughties caused a problem for the ECB, not least when some teams fielded up to half a dozen southern Africans in their XIs. This was countered by the ECB's stiffening of the qualification criteria, working in conjunction with the Home Office.

Since 2009, only those players with a Test cap in the preceding 12 months or five in the previous five years have been able to turn 'Kolpak'.

Although that has undoubtedly led to an increase in the standard of county cricket, lured by opportunities to cash in on he strength of sterling compared to their own weak rand, it has also ripped players of the calibre of Olivier, Kyle Abbott and Rilee Rossouw from the bosom of the South Africa team.

It will, however, barring successful legal challenges, be a thing of the past from the 2021 season onwards in any Brexit secured by Boris Johnson's new administration.