LONDON — Best-selling British espionage writer David Cornwell — known to the world as John le Carré — died Saturday at 89, according to his literary agent.

A statement shared on behalf of the author's family said: "It is with great sadness that we must confirm that David Cornwell — John le Carré – passed away from pneumonia last Saturday night after a short battle with the illness.

"David is survived by his beloved wife of almost 50 years, Jane, and his sons Nicholas, Timothy, Stephen and Simon.

"We all grieve deeply his passing. Our thanks go to the wonderful NHS team at the Royal Cornwall Hospital in Truro for the care and compassion that he was shown throughout his stay. We know they share our sadness."

The statement said his death was not COVID-19 related.

"I represented David for almost 15 years. I have lost a mentor, an inspiration and most importantly, a friend," said Jonny Geller, CEO of literary agency The Curtis Brown Group. "We will not see his like again."

Described by Geller as the "undisputed Giant of English literature," le Carré wrote 26 books that have been published in over 50 countries and 40 languages, according to his official website.

Le Carré was born in 1931 and attended the universities of Bern and Oxford. He also served briefly in British Intelligence during the Cold War. His most famous works spanned some six decades and included "The Spy Who Came In Form the Cold," which was published in 1963 and made le Carré "the most famous spy writer in the world," Geller said.

Le Carré also wrote "Tinker Tailor Solider Spy" and "A Mo.st Wanted Man," which were made into blockbuster movies, according to CNN

Authors took to social media to mourn le Carré. "This terrible year has claimed a literary giant and a humanitarian spirit," Stephen King tweeted.

British historian and author Simon Sebag Montefiore tweeted he was "heartbroken" over le Carré's death, calling him a "titan of English literature" who was up with the greats.

British actor and writer Stephen Fry tweeted he was unable to name a contemporary writer who has given him more "richer pleasure" than le Carré.

"I suppose the best one can do to honor his great life & talent is go back to 'Call For The Dead' and reread all his books," Fry wrote. "The very opposite of a chore."

Several of le Carré's 25 works were turned into films including The Constant Gardener, The Tailor of Panama and Tinker, Tailor, Soldier, Spy, while the Night Manager became a successful BBC television series.

His most famous character, George Smiley, who first appeared in Call for the Dead, has been played by actors including Rupert Davies, Alec Guinness and Gary Oldman, a BBC report stated.

Historical fiction writer Robert Harris said he was "one of the great post-war British novelists" and "an unforgettable, unique character".

Actor Oldman, who appeared in the 2011 film of Tinker, Tailor, Soldier, Spy, said le Carré was "a very great author, the true 'owner' of the serious, adult, complicated, spy novel" and was "always a true gentleman".

Author Margaret Atwood tweeted that the Smiley novels were the "key to understanding the mid-20th century".

Le Carré described himself as "English to the core" but deplored what he saw as the aggressive nationalistic sentiment behind Brexit.

"My England would be the one that recognizes its place in the EU. The jingoistic England that is trying to march us out of the EU, that is an England I don't want to know," he said. — Agencies