Ian Gelder, the British actor best known for his roles in Torchwood and Game of Thrones, has died only months after being diagnosed with cancer.

The 74-year-old found out in December that he had bile duct cancer, and his health declined rapidly.

Gelder’s husband Ben Daniels shared the devastating news on Instagram.

“It is with huge huge sadness and a heavy heart broken into a million pieces that I’m leaving this post to announce the passing of my darling husband and life partner Ian Gelder,” he wrote.

“Ian was diagnosed with bile duct cancer in December and yesterday he passed at 13.07.

“I’d stopped all work to be his carer but neither of us had any idea that it would all be so fast.”

Daniels and Gelder had been together for more than 30 years.

“If we weren’t together we spoke to each other every day,” he wrote.

“He was the kindest, most generous spirited and loving human being.

“He was a wonderful wonderful actor and everyone who worked with him was touched by his heart and light.

“I honestly don’t know what I’ll do without him by my side.”

Gelder’s acting career spanned decades on the screen and stage.

He had roles in Torchwood: Children of Earth in which he played Mr Dekker and appeared in 12 episodes of the cult hit Game of Thrones before his character, Kevan Lannister, was killed off.

His stage credits include numerous credits in productions on London’s West End and Shakespeare’s Globe Theatre.

Daniels said his partner had coped with his dreadful illness with bravery and no self pity.

“He was remarkable and will be so missed.”

He posted a photo taken at Christmas, just after Gelder left hospital.

“Even though he’d gone through the worst three weeks there you can still see his joy and love shining through.”