Is one being served? Not in here...

We may be allies in war, but Brits trying to shop on an American airbase will find that access is strictly denied - even if one of them is Prince Harry.

Being third in line to the throne should mean the prince has no problem getting served in shops - but that was not the case when he paid a surprise visit to a US airbase.

The 22-year-old prince, who has been training in Norfolk this week ahead of a posting to Iraq, found himself in a tricky situation with some army colleagues as they tried to buy an Ipod from the exchange shop at RAF Lakenheath in Suffolk on Sunday.

Sources at the airbase said the prince entered the shop wearing full Army uniform accompanied by colleagues and his bodyguard.

One of the prince's friends then tried to buy an Ipod but was turned away because he was not a US servicemen or family member at the American airbase.

Lt Col David A Konop, US forces spokesman , said staff did not recognise the prince.

"The girl at the till just did not recognise the prince at all," he said. "I know all the staff were surprised when they realised who had been in the store.

"We're just really proud and pleased that Prince Harry chose to step on to our base and in the store. As you can imagine, the visit has created a lot of interest on the base as most Americans are fascinated with the British royal family."

Prince Harry is due to deploy to Iraq in the summer and recently underwent training at Stanta, near Thetford, as part of his preparation.

A Clarence House spokesman declined to comment on the impromptu shopping trip. However, an MoD spokesman was slightly more forthcoming.

"We do not usually comment on individual officers, but we can confirm that UK and military personnel in the UK are not entitled to use this shop."

Lt Col Konop later said the prince had been planning to buy something, but put the item back after the group was told they could not buy anything.

"He was in the line and was going to purchase something, although I don't know what was in his hand at the time," he said.

"Once the first soldier got turned away all three of them went back and put the items back on the rack... The prince didn't identify himself and there was no issue at the time."

Lt Col Konop said it was possible staff did not recognise the prince.

"He looks like a soldier in uniform," he said.

But he added: "I bet a few people there said to themselves 'I bet that's the prince' but didn't have the nerve to say anything."

Lt Col Konop said that if the prince had made his presence known he could have bought what he wanted.

"I am told three or four distinguished visitors from the British Army come monthly and are allowed to shop there, so it would not have been considered special treatment," he said.