The British Horseracing Authority is hoping that the European Union continues with the current method of transporting horses overseas even if there is a no-deal Brexit.
With the United Kingdom due to leave the EU on March 29 the first major meeting to be threatened by any new ruling would be the Grand National at Aintree which begins on April 4.
At the moment horses who have an equine passport are free to move between Britain and Ireland and currently horses do not need to travel via a Border Inspection Post.
However, if Britain does leave the EU without a deal, there is a chance horses who arrive from overseas will not be allowed to return home, according to guidance from the Department for Environment, Food and Rural Affairs.
BHA Executive Director Will Lambe said: “We welcome the fact that the UK will not be changing the current successful systems for the movement of thoroughbreds immediately in the event of no deal.
“The guidance note reflects the constructive discussions we have been having with Defra officials and Ministers for a number of months, and in particular the fact that the current systems work well in terms of maintaining high health and welfare standards, and facilitating trade and international competition.
“However, were the EU not to also replicate these current systems, the implications are clear, and stark. There would be disruption, and significant cost, with the impact falling principally on EU members.
“We hope as such that the mutual interest in sensible arrangements being reached can prevail, and indeed that a deal is secured in the coming weeks that would trigger an implementation period through to the end of 2020 during which the tripartite agreement would continue.
“With a full set of no deal notices from the UK government now published we will be completing our detailed assessment of each in terms of implications for our sector and issuing our own summary and guidance to Racing and Breeding stakeholders and participants in the next couple of weeks.”