The founder of the Virgin Group had revealed Templeman’s death, aged 80, in an Instagram post late Tuesday, saying he was “heartbroken”.

He did not say what had caused her passing, but noted in a subsequent blog post that she had recently been recovering from a back injury in hospital in England.

Eulogising their decades-long relationship, Branson said they had enjoyed “fifty incredible years of memories”.

“Years filled with tears and laughter, kindness, and a love that shaped our family more than words could ever capture,” he added in the message, shared on his Virgin Group’s website.

“It was a relationship that worked. We just had lots of laughs. We were very lucky.”

Branson said the family — which includes their two adult children, Holly and Sam, and several grandchildren — were “devastated” at the loss.

The couple first met in London in 1976, with the tycoon previously saying he had fallen in love with Templeman at first sight.

They married 13 years later, on the private Necker Island in the Caribbean, which Branson had bought in the late 1970s for US$180,000 and where they have lived for decades.

Templeman avidly avoided the public spotlight, with Branson describing her as a “down-to-earth Scottish lady” and “very private person” who almost never gave interviews.

In his post Wednesday, he said she “lived so fully and joyfully, always thinking of others, always lifting everyone else up”.