Defying Chinese outrage, exiled dissidents, ambassadors from dozens of countries, Norwegian royals and other dignitaries will gather around an empty chair Friday to hail absent Nobel Peace laureate Liu Xiaobo.

Beijing has reacted with fury to the award of the peace prize to Liu, describing the Norwegian Nobel Committee as "clowns," and threatening other countries to stay away from the ceremony, while preventing the jailed dissident or a representative from travelling to Oslo to receive the award in person.

"Dr Liu's chair will be conspicuously empty at today's award ceremony," Irwin Cotler, a member of Liu's international legal team, said in a statement just hours before the ceremony was to kick off in the Oslo city hall at 1:00 pm (1200 GMT).

Friday marks only the second time in the more than 100-year history of the prize that neither the laureate nor a representative will be able to accept the award.

The only other time was when German journalist and pacifist Carl von Ossietzky, who was locked up in a Nazi concentration camp, could not travel to Oslo for his prize ceremony in 1936.

Like Ossietzky, who was a critic of the regime under which he lived, Liu has long been an outspoken opponent of Chinese leadership in Beijing.

The writer and former university professor was at the forefront of the 1989 Tiananmen Square protests.

He was jailed in December 2009 for 11 years on subversion charges after co-authoring "Charter 08", a manifesto that spread quickly on the Internet calling for political reform and greater rights in China.

Nonetheless, a large protest took place in front of the United Nations office in Beijing on Friday, international Human Rights Day and also the two-year anniversary since Liu published "Charter 08."

Amid Chinese pressure on countries not to attend Friday's ceremony, which the state media described as "a farce," confusion remained over which nations would be represented.

Nobel Institute director Geir Lundestad told AFP early Friday that the list of absentees was dwindling to under 20.

"Colombia, Serbia, the Philippines and Ukraine, which had been on the 'no' list, will be represented after all," he said.

In addition to China, the official list of absentees was made up of Afghanistan, Algeria, Cuba, Egypt, Iraq, Iran, Kazakhstan, Morocco, Pakistan, Russia, Saudi Arabia, Sudan, Tunisia, Venezuela, Vietnam and the Palestinian Authority.

In addition to placing an empty chair on the podium to represent Liu, he will be remembered with a photograph and one of his texts read by Norwegian actress Liv Ullmann.

He will receive his gold medal, Nobel diploma and prize money of 10 million Swedish kronor (€1.1 million, $1.5 million) at a later date.

The laureates of the Nobel prizes for chemistry, physics, literature and economics will collect their awards at a separate ceremony in Stockholm later Friday.