Moscow - Alexander Solzhenitsyn, the Nobel prize winner for literature who was exiled from the Soviet Union for his graphic portrayals of life in Soviet labour camps, was dead at age 89, the news agency Interfax reported early Monday.

The agency quoted literary circles in the Russian capital, where he was living since 1994 after the fall of the Soviet Union.

The world famous writer and historian had not been seen in public for months, and had reportedly been seriously ill for months. He died from the aftermath of a stroke, according to unconfirmed information.

Solzhenitsyn's main work was the massive Gulag Archipelago, first published in the West in 1973, which described the years of Stalinist terror using thousands of details and individual cases.

In 2007, the one-time exile received the highest Russian government award for his work in the humanities - the Russian State Prize.

In announcing the prize last year, Yury Osipov, president of the Russian Academy of Sciences, called Solzhenitsyn 'the author of works without which the history of the 20th century is unthinkable.'

One of Solzhenitsyn's first, most famous books, a slender volume called One Day in the Life of Ivan Denisovich, appeared in 1963 in English at the height of the Cold War.

It was the story of a former prisoner of war caught by the Germans during World War II, then returned home only to face charges of being a spy - a fate that awaited many POWs returning home to the Soviet Union.

The massive Gulag Archipelago, published in the west in 1973 and circulated in samizdat - or underground - publication within the Soviet Union, turned the world's attention to the horrors of the Soviet gulag system.

That book led to Solzhenitsyn's exile from his homeland in 1974.

Solzhenitsyn did not attend the announcement of the state prize in Moscow's Kremlin in 2007, but his wife Natalya said the writer hoped his study of Russia's history would help the country in the future.

The prize, she said, 'gives a certain hope, and Alexander Isayevich (Solzhenitsyn) would be glad if that hope came to life, a hope our country will learn the lesson of its self-destruction in the 20th century and not repeat it.'

The State Prize's origins date back to Soviet times, but Solzhenitsyn was just the second person to receive the prize for work in the humanities.

Russian Orthodox Patriarch Alexiy II received the first such prize in 2006.