According to the Committee's motivation, Obama has meant that international diplomacy has regained its central position, with an emphasis on the role of the UN and other international bodies can play.
"Only very rarely has a person to the same extent as Obama captured the world's attention and given its people hope for a better future," Jagland said.
Jan Egeland, director of the Norwegian Institute of International Affairs, has welcomed the award:
Barack Obama wins the Prize after less than a year in office. He is the third senior U.S. Democrat to win the prize only in this decade, after former Vice President Al Gore won in 2007 along with the U.N. climate panel and Jimmy Carter won in 2002.
Among the Swedish reactions to Obama as this year's Nobel Peace Prize laureate we find the leader of the Conservative's group in Parliament, Lars Lindblad. He tells the news agency TT that it might be "historic mistake".
"In my opinion the Peace Prize should go to someone who has done something. Now the prize is given to Barack Obama without the US having done any forceful commitments ahead of the climate meeting in Copenhagen. In the meetings we have had with the US, there are ever stronger signals that the US is not prepared to act," Lindblad said.
Also Urban Ahlin, the Foreign Policy spokesperson of the main Swedish opposition party, the Social Democrats, expressed surprise at the Nobel Committee's decision.
"The efforts Barack Obama has shown for peace do not match a peace prize," Ahlin told TT.
"He has given an end date to Iraq, but fighting still goes on. The war in Afghanistan continue at full speed, and we have seen very little result of his initiative in the Middle East, and the Guantanamo Bay camp is still open. I would have liked to see Obama get the peace prize in a few years, when he had been able to show results of his efforts. As it stands now, it is very early," Urban Ahlin said.
The Swedish Peace and Arbitration Society, Svenska Freds, also criticised the decision, with their chairman Anna Ek saying someone conducting two wars around the world shouldn't get the peace prize.
The head of Sweden's own Peace Research Institute Dr Bates Gill, says he was surprised by the win, but is hopeful it will help the American President.