With a record 199 individuals and organisations nominated for the prize, the list of possible laureates is a patchwork of names, featuring Irish U2 rock star Bono, former US secretary of state Colin Powell and non-governmental organisation Oxfam.

Former Finnish president Martti Ahtisaari could be rewarded for his success in brokering a peace agreement between the Indonesian government and Aceh rebels this year, ending 30 years of conflict in the troubled province.

But many feel this year's prize, which will be announced in Oslo on October 7, will go to a person or group working to halt nuclear proliferation, as the issue has been in the international spotlight over the past year, largely due to thorny negotiations with Iran and North Korea.

The Nobel committee could well choose to honour Nihon Hidankyo, a Japanese organisation of survivors of the Hiroshima and Nagasaki nuclear bombs, only weeks after the emotional 60th anniversary commemorations of the devastating bombings in both cities.

The International Atomic Energy Agency, IAEA, is also again in the running, as are US Senator Richard Lugar and former Senator Sam Nunn, whose Cooperative Threat Reduction (CTR) programme works to dismantle nuclear missiles and submarines to secure fissile materials in the former Soviet Union.

Last year, the Peace prize went to Kenyan ecologist Wangari Maathai, the first African woman to win the award, for a tree-planting project in Africa where deforestation has been a major problem.

The literature prize has for decades gone to fiction writers and poets, but some say it could be time to stray back into a different genre, possibly honouring a writer mixing fiction and non-fiction.

"The Academy has spoken of wanting to broaden the prize, which could open the door for instance for literary journalists like Polish Ryszard Kapuscinski," said Eva Bonnier, head of Sweden's Bonnier publishing house.

Among past non-fiction writers and non-poets winning were Bertrand Russell in 1950 for his philosophical writings and Winston Churchill three years later for his historical accounts.