An anti-racism group has condemned a Premier League football club for the punishment imposed on a fan who made Nazi salutes at a match.

The 39-year-old supporter was arrested on suspicion of racial and religious harassment the day after the clash with Tottenham Hotspur at St James’ Park in August.

Following a police investigation he was cautioned for repeatedly giving the salute and for motioning with his hands as if turning on a tap — thought to be a reference to the gas chambers.

The man was identified after fellow Newcastle fans contacted police and the club to complain.

But the Hope Not Hate group said that the subsequent police caution, and a reported three-game ban issued by the club, were “weak.”

In a letter to Newcastle United chief executive Derek Lambias and Northumbria’s Chief Constable Sue Sim, Hope Not Hate’s Nick Lowles wrote: “This sanction was not strong enough and sends a poor message to other supporters.

“We are particularly disappointed, given the club’s strong and consistent anti-racist stance over many years. We would implore you to relook at this case and the decisions that led to the three-match ban and ensure stronger action gets taken in the future, both at a policing, Crown Prosecution Service and football level.”

A Newcastle United spokesman said: "The club can confirm that a man was arrested and cautioned by the police for a racially aggravated public order offence at the Spurs match and that he was immediately banned from attending the next three home Premier League matches.

"In reaching its decision to impose this ban the club took into consideration a number of factors, both aggravating and mitigating, however it is not prepared to expand upon such factors in this case."

He added: "Newcastle United are committed to dealing robustly with any reports of racist language or conduct at the stadium. The FA was grateful for the positive action taken by the club in this particular case."

A Northumbria Police spokeswoman confirmed that the caution had been issued and said: “Before any decision to issue a caution is made, the impact on the victim is considered and a caution is only issued if it is in the public interest to do so”.

Meanwhile there has been condemnation of the club’s £24 million shirt sponsorship deal with online money-lending business Wonga.

The leader of Newcastle City Council said that the deal was “sickening” because of Wonga’s high level of interest charges levied on loans, and the Football Association expressed its concerns.

The Muslim Council of Britain warned the club’s Muslim players that the new shirts would infringe Sharia laws on money lending and interest.

A Wonga spokesman said the firm was aware of the concerns, but the company’s Jewish founder, Errol Damelin, declined to comment on alleged antisemitic remarks that had followed the announcement of the deal.