Eurostar has angered customers by introducing tougher restrictions on the amount of alcohol that can be carried on board.
Under the new rules passengers cannot carry more than one bottle of wine or four cans of beer and spirits are banned.
This is despite alcohol being served at Eurostar stations and on board trains, and the firm’s website encouraging passengers to “bring back … a bottle or two from a chateau-hopping trip”.
Night trains or trains taking fans to and from sporting events will not sell alcohol or allow travellers to bring their own booze.
Rail expert Mark Smith, founder of Seat61.com, said Eurostar has “quietly changed its luggage policy” after previously having a “fairly easygoing” attitude to alcohol which saw only disruptive passengers and those travelling to ski destinations affected.
Passengers who want to carry spirits or more alcohol will have to use the luggage service, which charges a minimum fee of £30 per item.
Claire Tate, 40, from Newcastle, is on holiday in Belgium and was told she will not be allowed to carry a small, gift-wrapped bottle of whisky when she travels home - a decision that has left her furious.
Ms Tate described the policy as “disgusting” and said she will reconsider travelling by Eurostar in future.
“It’s meant to be easier and more friendly than flying,” she said.
“I think the policy is there for sports fans who come on drunk and disturb other holidaymakers. Something should be in place – like an extra fee – for those type of travellers.”
She was among dozens of passengers who took to social media to complain about the rule change.
Will Roberts wrote: “That’s crazy. You mean I can no longer bring a six pack of Belgian beer back home in my bag after a trip to Brussels? Is there a way to convince them to change?”
Maurits Wever said: “That’s a pity. We’re going on holiday to the Scottish islands of Arran and Islay. We wanted to buy some local whiskies, but these aren’t allowed on @Eurostar.”
Mr Smith of Seat61.com claimed it will be “completely unnecessary” to enforce the new measures on all trains.
“Eurostar has been around for over 20 years,” he said. “Why is (carrying alcohol) now a problem? I don’t believe society has changed that much.
“There’s an awful lot of people who are a bit shocked that they could be caught out. They’re shocked that they won’t be able to bring back a couple of bottles of nice wine from Paris or some fascinating Belgian beers from Brussels.”
He added: “It’s going to be inconvenient for a lot of passengers. It might not affect businessmen travelling first class who get (served) wine anyway, but it’s going to be a pain in the neck.
“I think air travel is a bit of a pain in the neck a lot of the time and we need a bit of respite.”
A spokesman for Eurostar said its luggage policy was updated last autumn to “maintain a pleasant environment on board for all our travellers”.
Passengers who want to transport prohibited alcohol are advised to use the firm’s luggage service, which charges a minimum fee of £30 per item.