The chairman of the Nobel committee has defended the group's decision to award this year's Peace Prize to US President Barack Obama. Announcing the decision last week, the committee said it was honouring Obama for his drive to improve international diplomacy and his vision of a world without nuclear weapons. Commentators from all sides of the political spectrum were surprised by the announcement, with many saying Obama had not achieved enough to warrant such a prestigious awards. Critics have pointed out that he is still overseeing US military action in Iraq and Afghanistan. However, Thorbjorn Jagland, the chairman of the Nobel committee, says Mr Obama has done a lot to create a world with less tension. Speaking in Strasbourg today, he specifically cited the US President's efforts to reach out to the Muslim world and his plan to scale down his predecessor's plan for an anti-missile shield in Europe.