The 'Princess of Sealand' who ruled over a tiny platform in the middle of the North Sea has died aged 86.

Joan Bates was given the royal title for her birthday by her husband Roy after he occupied the platform in 1967 and declared it to be an independent country.

The Principality of Sealand continues to act as a sovereign state to this day - even issuing its own currency with Mrs Bates's head on it.

Princess: Joan Bates, pictured left in the 1960s and right with her husband Roy, has died aged 86

Realm: The couple ruled over this platform in the North Sea, which they christened the Principality of Sealand

Map: The platform has been governed as an independent country despite being just a few miles from the coast

The Princess passed away at a nursing home in Leigh-on-Sea, Essex last week after a long illness.

Her son Michael, 63 - the current Prince of Sealand - paid tribute to his mother and her role in establishing the rogue principality nearly 50 years ago.

'My mother was a stunning woman,' Mr Bates said.

'She was born in Aldershot Barracks and her father was in the Royal Horse Artillery and they were later stationed at Shoebury Barracks.

'My father declared the independence of Sealand on her birthday on September 2, 1967, giving her title of Princess.'

Rulers: Mr and Mrs Bates took over the platform in 1967 in order to set up a pirate radio station there

At work: Mrs Bates pictured dangling in a crate off the side of the platform in the early days of Sealand

Currency: Sealand's coins feature the head of Princess Joan and are considered collectors' items

Sealand is a military fort built during the Second World War six nautical miles off the coast of Essex.

It was due to be demolished after the end of the conflict, but instead Roy Bates took it over in order to operate Radio Essex, a private radio station.

Along with his wife and their teenage children Michael and Penny, now 66, the DJ continued to live on Sealand for years.

He faced opposition from the British Government, who feared that the platform could become a Communist state like Cuba.

However, in 1968 a judge ruled that 'the UK courts have no jurisdiction' over Sealand, allowing the Bates family to continue to run the territory as an independent country.

Family: Mr and Mrs Bates pictured with their son Michael, second from right, and friends Barry Harcuss and Gordon Wilkinson

Descendants: Michael Bates later lived on the platform with his wife Lorraine and their daughter Charlotte

Michael Bates, who has lived on the platform with his wife and daughter in recent years, said his mother had been an essential to establishing the Sealand project.

He said: 'My mother was a natural beauty who devoted her life to her husband. A former carnival queen and model, Joan led quite a high profile life alongside my father.

'She became engulfed by the offshore pirate radio phenomena, helping to establish Radio Essex. She did a lot for charity throughout her life, particularly the RNLI.'

Mrs Bates's grandson James, 29, added: 'Grandma was lovely and full of life. She was always immaculately turned out and very glamorous. She modelled for all sorts of companies.

'I used to spend a few weeks a year on Sealand. Dad was only 12 when he first went to Sealand. He never made a big thing of it so we didn't either, but when I told friends about it, they were always amazed.'