Winds of Winter Release Date Latest News: 'Games Of Thrones' New Book Will Not Come In 2015, Confirms Publisher

Fans of George RR Martin's books will have to wait a little while longer after Game of Thrones publisher HarperCollins confirmed that the sixth book in the bestseller series, "Winds of Winter," would not be coming out this year.

HarperCollins executive Jane Johnson defended the delay in the writing of the novel saying "these are increasingly complex books and require immense amounts of concentration to write," The Guardian reported on Friday. "Fans really ought to appreciate that the length of these monsters is equivalent to two or three novels by other writers," Johnson added.

Die-hard fans have been waiting for years as the fifth book, "A Dance With Dragons," was published way back in 2011.

Instead, fans would have to be content with the illustrated version of the three previously anthologized novellas which also take place in Westeros, the Guardian said.

This compilation of "The Hedge Knight," "The Sworn Sword" and "The Mystery Knight," three official prequels to the series, will be out on October.

"The novellas are illustrated in black-and-white line drawings throughout by Gary Gianni in classic style. It will be a truly lovely book, and I adore these clever, funny stories," said Johnson.

George RR Martin has come under fire for his slow development of the next book in the series amid fears that the hit HBO show, which is based on the books, will outrun the publication.

In July, the books' author lashed out to impatient fans who worry he might not finish his fantasy series "A Song of Ice and Fire" before he passes away.

"I find that question pretty offensive, frankly, when people start speculating about my death and my health," he told the Swiss daily newspaper Tages-Anzeiger in an interview.