BERLIN, March 4: Nazi Germany was not only trying to develop nuclear weapons but actually tested atomic devices near the end of World War Two, the publisher of a yet to be released book by a German historian says.

The pre-publication claims by historian Rainer Karlsch drew headlines in German newspapers on Friday but the publisher of "Hitlers Bombe" (Hitler's Bomb) declined to give details or answer further questions until the book is launched on March 14.

Other historians played down any suggestion the Nazis were anywhere close to taking on the US in a nuclear war. According to the publisher, Mr Karlsch says Nazi scientists tested "nuclear bombs" in 1944 and 1945 on the Baltic island of Ruegen and in central Germany under the supervision of the SS, but they were not ready to be deployed before the war ended.

Bernhard Fulda, a lecturer on 20th Century German history at Cambridge University, said even though Germany's interest in harnessing nuclear energy was well known, the idea that the Nazis almost won the nuclear arms race was implausible.

"I would dismiss any suggestion that these were tests comparable to those carried out by the Americans as part of the Manhattan project," he said, referring to the secret programme that led to the Hiroshima bombing of Aug 1945.

Mr Karlsch has been on the staff of Berlin's Free and Humboldt universities, publisher DVA said. A DVA spokesman said the book was based on research reports, construction plans, diaries, aerial photos, spy reports and testimonies of some of the scientists involved.

"Under the supervision of the SS, German scientists tested nuclear bombs on Ruegen and in Thuringia in 1944 and 1945," the spokesman said. Hundreds of prisoners of war and internees died during this process, he added.

QUESTIONS: Radiation measurements and soil analysis were also used to back up the assertions, he said. The publishing house said the book asserts there was an operational nuclear reactor close to Berlin in 1944-45, and that Nazi physicists had drafted a patent for a plutonium bomb as early as 1941.