The prestigious prize will be announced on Friday, October 10 but before that, Trump's assault on science is likely to stir debate when the laureates for the medicine prize are revealed on Monday, followed by daily announcements for the awards for physics, chemistry, literature, and economics.

Trump said this week it would be an "insult" to the United States if he did not win the Nobel Peace Prize, but experts in Oslo, where the award is based, say he has virtually no chance due to his "America First" policies and divisive style.

"It's completely unthinkable," Oeivind Stenersen, a historian who has conducted research and co-written a book on the prize, told AFP.

Trump "is in many ways the opposite of the ideals that the Nobel Prize represents", he said.

"The Nobel Peace Prize is about defending multilateral cooperation, for example in the UN... and Trump breaks with that principle, he follows his own path, unilaterally," he added.

The US leader claims to have resolved six or seven wars in as many months -- a figure experts say is grossly exaggerated.

"The Nobel Committee should assess whether there have been clear examples of success in that peacemaking effort," the head of the Stockholm International Peace Research Institute (SIPRI), Karim Haggag, told AFP.

Tens of thousands of people are eligible to submit a candidate for the Nobel Peace Prize.

This year, 338 individuals and organisations are known to have been nominated but their names are kept secret for 50 years.

- Forgotten conflicts -

Haggag said the prize ought to go to actors working quietly behind the scenes.

The Nobel Committee should shine a light on "the work done by local mediators and local peace builders on the ground", he said.

"These are actors who have been forgotten in many of the world's forgotten conflicts," he said, citing Sudan, the Sahel and countries in the Horn of Africa -- Somalia, Ethiopia and Eritrea.

Sudan's Emergency Response Rooms -- networks of volunteers risking their lives to feed and help people enduring war and famine -- are one such group, he noted.

Media watchdogs such as the Committee to Protect Journalists and Reporters Without Borders could also be honoured after a deadly year for reporters, especially in Gaza.

"Never before have so many journalists been killed in a single year," Nina Grager, the head of the Peace Research Institute of Oslo, said.

Yulia Navalnaya, the widow of Kremlin critic Alexei Navalny, is meanwhile among bookies' favourites.

Last year, the Nobel Peace Prize went to Japan's atomic bomb survivors' group Nihon Hidankyo for its efforts to ban nuclear weapons.

- Switzerland's Kracht for literature? -

The other Nobel that generates frenzied speculation is the literature prize, to be announced on October 9.

Switzerland's Christian Kracht, considered one of the greatest contemporary authors in the German-language world, is a favourite in literary circles.

At this year's Gothenburg Book Fair, held annually a few weeks before the Nobel prize announcement, "many members of the Swedish Academy (which awards the literature prize) were there, sitting in the front row during his event", culture critic Bjorn Wiman at Swedish daily Dagens Nyheter told AFP.

"And that is usually a sure sign," he said.

After the Academy gave the nod to South Korea's Han Kang last year, Wiman thinks this year "it will go to a white man from the Anglo-Saxon, German or French-language world".

The Nobel season opens Monday with the medicine prize, followed by the awards for physics on Tuesday and chemistry on Wednesday.

The economics prize wraps up the Nobel season on October 13.

The mechanisms of innate immunity, the identification of leukaemia stem cells and the discovery of an appetite-regulating hormone are among the medical research fields that could be honoured.

This year's laureates in the science disciplines could use their win to sound the alarm over Trump's billions of dollars of funding cuts for scientific research.

The Nobel Prize consists of a diploma, a gold medal and a cheque for around $1.2 million.