OSLO • The Nobel Peace Prize is not due to be announced until tomorrow, but several names have already surfaced as the possible winner this year - including German Chancellor Angela Merkel, Pope Francis and a Russian newspaper.

The only one of the six Nobel prizes to be awarded in Oslo - the others are announced in Stockholm - the Peace Prize is the one that garners the most attention and speculation. But predicting the winner is largely a game of chance, as the list of nominees is kept secret for 50 years.

This year, 273 names are known to be on the list.

Dr Merkel has been tipped as a favourite for her decision to admit at least 800,000 refugees into Germany amid the migrant crisis.

"Angela Merkel is the one who really took a moral leadership," the head of the Peace Research Institute of Oslo, Mr Kristian Berg Harpviken, was quoted as saying by Agence France-Presse.

The Pope is a possible contender for his work in brokering this year's detente between Cuba and the US, while Russian newspaper Novaya Gazeta has distinguished itself for being an independent voice under President Vladimir Putin's rule.

Among the others said to be in the running are Congolese doctor Denis Mukwege, who has treated thousands of victims of sexual violence, and Eritrean Catholic priest Mussie Zerai, who helps rescue migrants crossing the Mediterranean, reported The Telegraph.

The Nobel committee may also reward the architects of Iran's recent nuclear deal, including US Secretary of State John Kerry and his Iranian counterpart Javad Zarif, said Mr Peter Wallensteen, a professor at Uppsala University.

Whatever the outcome, the result is likely to be controversial.

A win for Dr Merkel, for example, would anger those who say her refugee policy is making the migration crisis worse. A win for Novaya Gazeta is unlikely to go down well with the Kremlin, while a win for the Pope will anger those opposed to his views on birth control, said The Telegraph.