The largest gurdwara in Europe is renowned for its hospitality and its open door policy welcoming all, irrespective of race, religion or creed.

So it was a slap on the face for the trustees of the Gurdwara Sri Guru Singh Sabha in Southall, West London, when they were told that a senior London policewoman had warned her fellow officers to avoid gurdwara food because it was unhygienic.

The warning, leaked to the Guardian newspaper, stemmed from last November's Nagar Kirtan celebrations to mark the 534th birthday of Guru Nanak when volunteers prepared langar for all, including the police.

The trustees, who have hosted Prince Charles, successive commissioners of Scotland Yard and scores of other dignitaries, cannot believe that their tradition of generous hospitality is now being spurned by the unnamed policewoman.

"This is not right, this is very bad," gurdwara president Himmat Sohi told rediff.com "Of course we are very hurt. She has no right to say that sort of thing."

The gurdwara has celebrated at least a dozen Nagar Kirtans, but this is the first time there has been any kind of complaint about the quality of the food.

Sohi says he heard about the complaint when a Guardian reporter contacted him earlier this week.

The newspaper was the recipient of a leaked report from within Scotland Yard in which the policewoman told her colleagues to stay away from the gurdwara because "the hygiene standards are not as good as ours".

"Let this be a matter of discipline for the met (metropolitan force). One bad apple is not representative of all the police. Of course, if she is not disciplined we will take action," Sohi said.

Senior Scotland Yard officers anxious to recruit more police from Britain's ethnic minorities are hoping the controversy will not get out of hand and poison relations with the Sikh community.

The police are still smarting from the experience of Gurpal Singh Virdi, who was falsely accused of writing racist hate mail and dismissed from the force in March 2000. After an employment tribunal ruled he had been unfairly treated, he was taken back into the force and paid £240,000 in compensation.