Fans who chant abuse face ban - West Ham
West Ham have warned their supporters that anyone found "acting inappropriately" at this weekend's London derby away to Tottenham Hotspur risk a ban.
Fridays statement by the Hammers comes after police warned fans of both clubs that anyone found chanting "Yid" at White Hart Lane on Sunday could be arrested.
"A London derby is always a passionate affair and, as ever, we know the players will be backed by a loud and proud travelling support," West Ham said.
"However, the club seeks to remind all fans attending the match at White Hart Lane that they will be acting as ambassadors for West Ham United and their behaviour should reflect the values and standards of our club."
For years, sections of Tottenham's support have described themselves as 'Yids', in a bid to reclaim the pejorative term from anti-Semitic opposition fans who have used it to make slurs about north London club Spurs' longstanding links to the Jewish community.
However, in its desire to clamp down on discrimination in the English game, the Football Association has asked Tottenham supporters to refrain from chanting 'Yid'.
In November, police launched an investigation into claims that during a match against Spurs, West Ham fans had chanted the name of Adolf Hitler and imitated the noise of Nazi death camp gas chambers.
Two West Ham supporters were cautioned by police and one of them was given a lifetime ban by the east London club, whose co-owner, David Gold, has Jewish ancestry.
In a bid to prevent such incidents on Sunday, London's Metropolitan Police Service warned fans on Thursday of the consequences of chanting 'Yid' this weekend.
"Some words - like the 'Y' word -- which historically have been perceived by some as acceptable, cause harassment, alarm or distress to others, and people who use this language could be committing a criminal offence," said a statement.
Rival fans have sometimes used Spurs' Jewish connections -- current chairman Daniel Levy is the latest in a line of Jewish businessmen to have guided the club -- as a way of baiting Tottenham fans.
Chief Superintendent Mick Johnson, the match commander on Sunday, added: "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."
Last month Prime Minister David Cameron found himself drawn into the row when, in an interview with the Jewish Chronicle newspaper, he said Spurs fans using the word "Yid" should not be prosecuted.
Cameron said there was a difference between Spurs fans "self-describing themselves as Yids and someone calling someone a Yid as an insult".
Tottenham and England great Jimmy Greaves, Spurs's record goalscorer, said he was proud to be called a 'Yid' and was prepared to be arrested for joining in with the chants.
The 73-year-old Greaves, who is not Jewish, told the Sunday People last month: "People are trying to sanitise a situation for no reason whatsoever and if they are going to get arrested then I am going to stand up and shout it myself so I can be arrested as well.
"Do you seriously think that Tottenham supporters are chanting it as a racist remark?"