Game Of Thrones creator George R. R. Martin has refused to kill off a British teenager in the next instalment of his hit book series.

The author offered to create two new characters based on fans who donated $20,000 (Gbp11,700) to a recent Prizeo campaign to benefit Santa Fe's Wild Spirit Wolf Sanctuary - and write them off in the next Game of Thrones book.

The prizes were quickly snapped up by an anonymous female and Facebook employee Dave Goldblatt, but one 13-year-old fan wanted to be included too and wrote to Martin, begging for a grisly death in his new book.

The kid also offered up $260 (£153) from his savings to Martin's wolf sanctuary cause.

The young fan wrote, "Wolves are my favourite animal, and when I grow up, I want to be a wolf conservationist... Maybe you have heard of the Wolf Conservation Trust near Reading in the U.K."

But the writer has declined the offer, telling the teenager, "There's a limit to how many people even I can kill."

However, Martin has been inspired by the 13 year old's donation, and he has pledged $10,000 (£5,900) to the U.K. Wolf Conservation Trust in the boy's name.

He writes, "I’ve heard that you donated all your £153 pocket money savings to my Prizeo fundraiser on behalf of the Wild Spirit Wolf Sanctuary. I cannot tell you how much that moved me. It pleases me no end to know that my novels, and the Tv series based on them, have inspired readers as young as yourself to rally to the support of these majestic and too often stigmatized animals."