The Metropolitan Police has been ordered to withdraw its claim to be “the oldest police service in the world” after the advertising watchdog ruled that the Glasgow force had been around longer.

A complaint was made to the Advertising Standards Authority after the Met advertised for royal protection police in newspapers last month, stating: “We’re not just the oldest police service in the world. We’re also the most modern.”

The complaint, which is believed to come from a long-serving Glasgow officer, said that the City of Glasgow Police were set up in 1800 - 29 years before the Metropolitan Police force was formed under Sir Robert Peel.

The ASA said: “A reader believed that the advert was misleading because he understood that the City of Glasgow police force preceded the Metropolitan Police.”

The authority told the force that it had considered the complaint under three sections of its code of practice: substantiation, truthfulness and comparisons. After receiving the warning letter, the Met immediately backed down and promised not to claim that it was the oldest force in the world again. The ASA then told the force: “We welcome your assurance that you are willing to amend the wording in your ad. We believe that this will resolve the complaint without the need for a formal adjudication and, on the understanding that you will remove the claim that the Metropolitan Police is the oldest police service in the world, we will now close our file.”

A spokesman for the Met said: “When the strapline was created we believed the information to be correct. The copy has now been amended. We are always pleased that our adverts receive attention and we welcome feedback.”

A Glaswegian police source said yesterday: “It’s a bloody cheek. You think they would check these things out first.”

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