Writing on his blog, author Martin said: "Another question that I get a lot, especially since the end of Game of Thrones on HBO, is whether A Song of Ice and Fire, will end the same way."
He added: "An architect would be able to give a short, concise, simple answer to that, but I am much more of a gardener. My stories grow and evolve and change as I write them.
"I generally know where I am going, sure... the final destinations, the big set pieces, they have been in my head for years... for decades, in the case of A Song of Ice and Fire.
"There are lots of devils in the details, though, and sometimes the ground changes under my feet as the words pour forth."
Martin then confirmed that the final two books in the series would not quite match up with what fans saw on screen: "What I have noticed more and more of late, however, is my gardening is taking me further and further away from the television series.
"Yes, some of the things you saw on HBO in Game of Thrones you will also see in The Winds of Winter (though maybe not in quite the same ways) but much of the rest will be quite different."
While largely faithful to Martin's existing books, the series also featured some large divergences from the source material such as Sansa Stark marrying Ramsay Bolton and excluding some characters like Lady Stoneheart.
Since the conclusion of the show in 2019, a number of spin-offs have been in the works including the soon to premiere House of the Dragon which will star Matt Smith and Paddy Considine.
A spin-off focussed on Jon Snow was also confirmed to be in the early stages of development.
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