Train journeys in England, Scotland and Wales will no longer be covered by Interrail passes from next year.
A dispute between the British rail industry and the European rail group means the Europe-wide unlimited rail passes will no longer be accepted in Britain.
However, the Eurostar between London and European cities is not affected.
BBC reports Northern Ireland is also not impacted, as it's covered by an all-Ireland arrangement.
The UK's Rail Delivery Group - which represents rail operators - said Eurail had decided to end their membership from January 1st, despite the British group wanting to remain a member.
They added that the decision is not linked to the UK's membership of the EU.
Interrail is not an EU scheme, and instead operates as an arrangement between the continents' rail operators.
Eurail, meanwhile, pointed to the introduction of a 'BritRail pass' for the decision - suggesting British operators had been working to secure a "competitive position" for their own pass.
Currently, a BritRail pass covering England, Scotland and Wales costs almost the same as an Interail pass covering the continent.
Eurail general manager Carlo Boselli said the organisation had done "everything within our reach" to persuade the British rail operators to remain within their two passes - Eurail (which covers non-European citizens) and Interrail (covering EU citizens and residents, as well as citizens from countries such as Russia and Iceland).
“I deeply regret that RDG’s priority to secure a competitive position for their BritRail Pass has led them to pull out of Interrail and Eurail"
Eurail’s General Manager, Carlo Boselli pic.twitter.com/Gt3Eymsb01— Eurail (@Eurail) August 7, 2019
In a statement, Rail Delivery Group's Robert Nisbet said: "Although the Eurail Group has ended our decades-long membership of Interrail since we stopped trialling Eurail passes, British people will feel no difference.
"They can still buy an Interrail pass, get the Eurostar and travel by train across Europe."
Interrail and Eurail Passes purchased before 31 December 2019 are still valid for travelling on Britain’s rail network until the end of their validity period.
— Rail Delivery Group (@RailDeliveryGrp) August 7, 2019
Liberal Democrats MEP Luisa Porritt described the move as "desperately sad".
She said: "This could lead to fewer young Europeans enjoying Britain and more barriers to Brits enjoying the rest of Europe."
British Labour peer Andrew Adonis, meanwhile, described the situation as 'shameful'.
The Interrail pass was introduced in 1972, covering most of Europe, and has expanded in the decades since.
It's most popular among young people, but passes are available for people of all ages.
The EU has been trialling free Interrail passes for 18-year-olds.