BERLIN - Nobel prize-winning German author Guenter Grass has admitted for the first time that he served in the Waffen-SS, Adolf Hitler's elite Nazi troops.

In an interview with the Frankfurter Allgemeine Zeitung, Grass, 78, said he volunteered for submarine service toward the end of World War Two. He was called up instead to serve in the Waffen-SS in the eastern city of Dresden.

German writer Guenther Grass, winner of the Noble prize in literature 1999, smokes his pipe during a news conferencein Frankfurt, in this October 15, 1999. Noble prize-winning German author Guenther Grass has admitted for the first time August 11, 2006, that he served in the Waffen-SS, the combat arm of the Nazi paramilitary group headed by SS chief Heinrich Himmler. [Reuters]

The author, best known for his first novel "The Tin Drum" and an active supporter of Germany's Social Democratic Party (SPD), said his wartime secret had been weighing on his mind and was one of the reasons he wrote a book of recollections which details his war service. The book is out in September.

"My silence through all these years is one of the reasons why I wrote this book," the paper quoted Grass as saying in a preview of its Saturday edition. "It had to come out finally."

One of the most powerful organizations in Nazi Germany, the SS played a key role in the Holocaust, establishing and operating the death camps in which millions died.

The Waffen-SS grew into a force of 38 combat divisions with almost one million men and it was condemned as part of a criminal organization at the post-war Nuremberg trials.

Grass was wounded in 1945 and sent to an American prisoner of war camp and later became a prominent peace activist. He said he had volunteered for army service as a way of breaking away from home and family.

"For me it was primarily about getting out of there. Out of that corner, away from my family," he told the paper.

"I wanted to put an end to that and that's why I volunteered for the army.

"It was like that for many of my generation," he added. "We were doing army service and then suddenly, one year later, the draft order was on the table. And then I realized, probably not until I was in Dresden, that it was the Waffen-SS."

Grass won the Nobel Prize for Literature in 1999. He is viewed as part of the artistic movement known in German as "Vergangenheitsbewaeltigung" or "coming to terms with the past."

Grass opposed the reunifaction of Germany in 1990, arguing that the country would be in danger of reverting to its role as a war-mongerer.