While George R.R. Martin is currently busy working on the next installment of his "Wild Card" series, book enthusiasts are eagerly waiting for "The Winds of Winter" release date. Inopportunely, the author is tight-lipped about its publication as he is in no rush to meet a particular deadline.

Now that "Game of Thrones" season 7 already bid its farewell on the small screens, many have concluded that the sixth book in "A Song of Ice and Fire" series may come out later this year or early 2018. Given that Martin is known for taking his time when writing the novels, the long wait shouldn't be much of a surprise to his followers.

The 68-year-old novelist has, to be fair, never been the speediest of writers, with his last book, 2011's "A Dance of Dragons," taking six years to write. But frustrations have enormously increased since Martin has given no definite answer about "The Winds of Winter" release date.

Martin said in a statement, "I did not start to write slower over the years. I was working on the first book for six years and four years on the second one. Fantasists who release their novels every year, do not offer books of large volume. These are not 1.5k pages like mine, but, for example, 500. In addition, I have not become younger. Age does not add enthusiasm."

Although the author made public that he had hoped the book would be out in advance of the sixth season of "Game of Thrones," he could not manage his time well due to his other responsibilities and age. He updated his fans on the progress of the novel back in July when he wrote on his LiveJournal that he's still working on it and that he has "good days and bad days, and that's all I care to say."

While everyone waits for "The Winds of Winter" release date, Martin divulged that he was almost ready to deliver a new volume of "Wild Cards" but publication date remains unknown. He did not specify whether he contributed to any of the stories or if his work was only limited to editing. So, in the meantime, his followers could read the upcoming volume as they wait for the highly-anticipated sixth book.