"There has been no specific request to make the programme more multi-cultural," an Entertainment Rights spokeswoman told BBC News Online.

Pat works in the fictitious village of Greendale

The BBC has also denied making any such request.

But the company said the series did have to be "redeveloped and refreshed" to keep up with "the changing lives of children".

"A brand needs to continually reinvent itself to keep its appeal," said the spokeswoman.

Success

Entertainment Rights bought the rights to Postman Pat after a �5.1m buy out of Woodland Animations in November.

The character, created more than 20 years ago by John Cunliffe, has been a long-standing success for BBC children's TV.

Mr Cunliffe was inspired to set the programme in the fictitious Lake District village of Greendale after he spent years working in the area.

No black characters have ever appeared on screen in Postman Pat's television run, although in the books Pat once worked with a Jamaican postlady.

The author has said that when he conceived the character there seemed to be no-one of Asian or West Indian origin living in Lake District area.

'Racial mix'

The Entertainment Rights spokeswoman said that the company did not know where the story about adding black characters had originated.

"I don't know where the story has come from and neither does John Cunliffe," she said.

"Postman Pat lives in a small Cumbrian village and it's not the same racial mix as a big city - but it's not something we're ruling out, either."

But Postman Pat fans are unlikely to see any changes soon.

"I doubt it will be next year - it takes so long to develop these ideas," said the spokeswoman.