West Ham and Spurs fans warned over 'Yid' abuse
Met Police officers will be on the lookout for supporters using the term 'Yid' in West Ham's clash with Tottenham on Sunday - and those responsible may be arrested.
It follows a debate over the term's use which last month Prime Minister David Cameron was dragged into.
He defended Spurs' fans use of the term but on Thursday the Met said it would not tolerate anyone chanting or shouting it.
In a statement it said: "Some words - like the 'Y' word - which historically have been perceived by some as acceptable, cause harassment, alarm or distress to others".
Chief Superintendent Mick Johnson, the match commander on Sunday, said: "This topic has been debated at length but our position is clear, racism and offensive language have no place in football or indeed in society.
"Those supporters who engage in such behaviour should be under no illusion that they may be committing an offence and may be liable to a warning or be arrested."
West Ham's co-owner David Sullivan also spoke out against the use of the word - often used by Spurs fans to describe themselves but seen as derogatory against Jewish people - and urged fans to behave at White Hart Lane.
He told The Mirror on Tuesday: ""We sincerely hope that a tiny minority of our supporters do not let us down.
"We are the only club that remembers the Holocaust each year and we have many Jewish supporters of our own.
"Sadly a few supporters, think it's funny to sing anti-Semitic songs and make anti-Semitic gestures. They need to realise in 2013 that it's not acceptable."
Tottenham are also encouraging their own fans not to use the term.