A fisherman has vowed to sue a Bicester fishery which has a sign banning Polish and "Eastern bloc" anglers.
Polish angler Rado Papiewski was horrified when he spotted the sign - and has now set up a crowdfunding appeal to get the sign scrapped and the fishery prosecuted.
Rado Papiewski. Rado, 35, told The Guardian: "When I first saw it I thought of my 10-year-old son who loves angling.
"How could I say to him you can't fish here because your dad was born in Poland?'
"This disturbing sign should have never been displayed as it clearly discriminates against people from Poland and other eastern European countries."
But the owner of the fishery at Lautnon near Bicester has refused to back down and said the sign had been erected after he caught some anglers stealing fish.
Mr Papiewski, who runs a project called Building Bridges for the Angling Trust, which aims to "educate and integrate" anglers from other countries has crowdfunded £5,000 to pay for a private prosecution and have the sign removed from Field Farm fisheries near Bicester.
He said: "It discriminates against a group of people. It could be any nationality on this sign. It's before my time but… people are commenting that this is like going back to the 1960s."
The Equality and Human Rights Commission said the sign was unlawful and it would take "enforcement action" if necessary.
The Building Bridges website explains that anglers from countries such as Poland have traditionally caught fish "for the pot", whereas in Britain anglers generally return fish to the water.
An Equality and Human Rights Commission spokeswoman described the sign as discriminatory and unlawful, and said it would be writing to the fishery to advise it to take it down.
"It's right to challenge such out of date practices and any business that believes this is acceptable should think again before they find themselves facing legal action," she said.
However fishery owner Billy Evans has defended the sign.
The former Conservative councillor, has had similar signs on his land since 2009 and said: "I shall still stand up for what I believe in.
"If they want to call me a racist for stopping thieves from coming on my private property that's what they'll do. "I know I'm right and I'm doing the right thing."