US President Barack Obama on Thursday accepted the Nobel Peace Prize, paying tribute to activists who have taken on governments around the world while uncomfortably acknowledging his role as a leader at war.
Obama's elevation to a pantheon of winners alongside the likes of Nelson Mandela, Mother Teresa and Martin Luther King before he has even spent a year in office has sparked international criticism.
Obama said he received the award with "great humility" and acknowledged the "controversy" saying that next to "some of the giants of history who have received this prize my accomplishments are slight".
He paid tribute to anti-government demonstrators in Iran, Myanamar and Zimbabwe and said the United States would always stand on the side of those who sought freedom.
"We will bear witness to the quiet dignity of reformers like Aung Sang Suu Kyi; to the bravery of Zimbabweans who cast their ballots in the face of beatings; to the hundreds of thousands who have marched silently through the streets of Iran," Obama said.
"It is telling that the leaders of these governments fear the aspirations of their own people more than the power of any other nation.
"And it is the responsibility of all free people and free nations to make clear to these movements that hope and history are on their side."
Responding to the international controversy over the award, the chairman of the Norwegian Nobel Committee, Thorbjoern Jagland, told the prize ceremony however that "history can tell us a great deal about lost opportunities."
"It is now, today, that we have the opportunity to support President Obama's ideas. This year's prize is indeed a call to action for all of us."
Obama is only the third sitting president to win the prize and he has been closely questioned about his credentials in Oslo, particularly after his decision to send 30,000 extra troops to Afghanistan.
He has admitted the timing of the award is an awkward coincidence.
Before the ceremony, he said: "I have no doubt there are others who may be more deserving."
But he told a press conference he would use the prize to bolster his pro-engagement foreign policy, and to work for lasting world peace.
"The goal is not to win a popularity contest or to get an award, even one as prestigious as the Nobel peace prize. The goal has been to advance America's interests," he said.
"If I am successful in those tasks, then hopefully some of the criticism will subside, but that is not really my concern.
"If I am not successful, then all the praise and the awards in the world won't disguise that fact."
The Nobel committee praised Obama for nurturing a new era of engagement and multilateralism in US foreign policy when it made its shock announcement in October.
Obama's first stop after landing in Oslo at dawn was to sign the guest book at the Norwegian Nobel Institute.
He marveled at how the award of the 1964 Nobel peace prize had galvanized the civil rights fight of Martin Luther King, who he has said helped pave the way for him to become the first African American president.
Obama lavishly praised Norway's hospitality amid disappointment in Oslo at his decision to cut short his stay, even leaving before an official dinner on Thursday night.
Disappointment in Norway was mirrored in the United States, where the US leader's once huge popularity has started to fray and isolationist sentiment is on the rise.
Several Norwegian peace and anti-nuclear organisations held demonstrations outside the award ceremony against a president who took office on a wave of euphoria but who critics say has fallen short of forging promised change.
Outside the Nobel committee offices, protestors held up a banner reading "Obama you won the prize, now earn it."
An InFact institute poll published Wednesday in the Verdens Gang daily showed just 35.9 percent of Norwegians thought Obama deserved the prize, down from 42.7 percent in October.
Nearly as many, 33.5 percent, believe the 44th US president is unworthy of the award that has been handed out for over a century.
In the United States, a Quinnipiac University survey of 2,313 registered voters published Tuesday showed that by a wide margin of 66-26 percent, Americans think Obama does not deserve the Nobel Peace Prize.
The medicine, physics, chemistry, economics and literature Nobel laureates will receive their awards at a ceremony in Stockholm on Thursday.
This video is from CNN's American Morning, broadcast Dec. 10, 2009.