Shoppers were shocked after they spotted the Queen seemingly doing her Christmas shopping in Fortum & Mason.

Camilla was seen browsing the tins of festive tea in the iconic department store - before settling on cinnamon and orange black tea, onlookers said.

Surrounded by a number of aids, Her Majesty was looking through the £13.95 tins for some time, shoppers claim.

Her visit on Tuesday carried on a long tradition of the royal family shopping at the store - which holds the royal warrant - at Christmas.

According to the website, "Her late Majesty Queen Elizabeth II continued the family tradition of doing Christmas shopping in store, which had to be arranged months in advance"."

She too favoured giving tea as gifts and the shop's website adds: "The list of provisions provided for her and her mother to give as presents reveal a shared practical bent of mind, with breakfast trays, breakfast sets, garden furniture and hostess trolleys being particularly popular."

Queen Camilla was spotted by a man who was in the store buying the same tea for his wife, at around 2.30pm.

He looked across the table and saw the Queen standing opposite him with the same tin.

The man, from Romford Essex, said: "It was great to be that close to her, and I never imagined I'd be asking after the same tea as the Queen."

"I just went to ask the attendant how much the tin of tea was and then I noticed she was standing right opposite me - I could hardly believe it."

"It was lucky chance. I'd gone in to London for a rare trip for my birthday."

"It was funny because I'd never have thought I'd be in touching distance of the Queen."

There must have been just over a metre between us.

"She had about four members of security with her but they didn't warn me off when I approached the table - that was a really good feeling."

It comes the day after she was spotted enjoying a night out at the theatre with her family, to watch Operation Mincemeat (16).

The Queen, 77, didn't commandeer the State Bentley for the private family gathering, however, instead opting for a Ford Transit minibus, reports said.