Colin Firth leaves Paddington Bear film

Colin Firth said when he was cast in September he would play the bear with a 'slight Peruvian flavour'

Oscar-winning actor Colin Firth has pulled out of voicing the upcoming Paddington film.

The King's Speech star said he had been unable to find the right voice for the Peruvian bear.

"After a period of denial, we've chosen 'conscious uncoupling'," Firth said in a statement, referencing the term Gwyneth Paltrow and Chris Martin made famous when they separated in March.

Based on the books by Michael Bond, the film is due to be released in November.

"It's been bittersweet to see this delightful creature take shape and come to the sad realisation that he simply doesn't have my voice," Firth told Entertainment Weekly.

"I've had the joy of seeing most of the film and it's going to be quite wonderful. I still feel rather protective of this bear and I'm pestering them all with suggestions for finding a voice worthy of him."

Paddington was named after the London train station where he was found by the Brown family

Paul King, the film's director, said the star's exit had been amicable.

"I cannot thank [Firth] enough for his contribution to Paddington," he said.

"We love the voice and we love the bear, but as our young bear came into being, we agreed that the two didn't seem to fit. So, with somewhat heavy hearts we decided to part ways."

King said a replacement would be announced in the coming weeks, promising the new actor would ensure Paddington's "big screen debut is magnificent".

The first trailer for the film was released in March, with a second released last week, however neither feature Firth's voice.

The movie also stars Nicole Kidman as an evil museum taxidermist who has Paddington in her sights, and Julie Walters and Hugh Bonneville as Mr and Mrs Brown - the marmalade-loving bear's adopted parents.