Obama defends 'just war' as he collects peace award

US President Barack Obama said conflict can sometimes be morally justified as he received his Nobel peace prize with deep gratitude and “humility” in Oslo, Norway. 

Warning that war is "never glorious, and we must never trumpet it as such," Obama argued that it could "sometimes be not only necessary but morally justified," saying negotiations would not end the threat from al Qaeda.

Obama said he received the award with "great humility". "Compared to some of the giants of history who have received this prize," he admitted, citing Martin Luther King and Nelson Mandela, "my accomplishments are slight".

The US president, who like other winners will get a diploma, a medal and 10 million krona (1.18 million euros), spoke at length on his responsibility fighting conflicts in Iraq and Afghanistan, where he has just announced the deployment of 30,000 extra troops.

"I am responsible for the deployment of thousands of young Americans to battle in a distant land. Some will kill. Some will be killed," he said.

"And so I come here with an acute sense of the cost of armed conflict - filled with difficult questions about the relationship between war and peace, and our effort to replace one with the other."

'You won the prize, now earn it'

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 debate.

Several Norwegian peace and anti-nuclear organisations held demonstrations outside the Oslo City Hall, where the ceremony took place. Protesters standing outside the Nobel committee offices held up a banner reading "Obama you won the prize, now earn it."

An InFact institute poll published Wednesday in the Norwegian Verdens Gang daily showed just 35.9% of Norwegians thought Obama deserved the prize and 33.5% said he was unworthy.

Obama has been closely questioned about his credentials since the Nobel committee made its shock announcement in October.

Responding to the international controversy over the award, the chairman of the Norwegian Nobel Committee, Thorbjoern Jagland, told the prize ceremony 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."

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 praised Norway's hospitality amid disappointment in Oslo at his decision to cut short his stay, snubbing a traditional luncheon with the king the day after the prize ceremony to return home.

Disappointment in Norway was mirrored in the United States, where the president's once huge popularity has started to fray and isolationist sentiment is on the rise.