"In a short time he has been able to set a new tone throughout the world and to create a readiness for dialogue," Merkel said, saying his efforts towards a world free of nuclear weapons should be supported.
Speaking on the edge of celebrations in Leipzig remembering the peaceful revolution in East Germany in 1989, Merkel said Obama had “opened a window of opportunity” for global diplomacy.
Germany's outgoing foreign minister, Frank-Walter Steinmeier, said the honour was an “important signal” for Obama's cooperative approach to international relations. Set to head the parliamentary opposition for the centre-left Social Democrats, Steinmeier said he was convinced Obama's “courageous policy” of dialogue was the best way “to break down the hardened fronts of many conflicts and promote the peaceful cooperation between peoples.”
Guido Westerwelle, Steinmeier's likely successor as Berlin's top diplomat, also congratulated the US president and urged “all those who have so far unfortunately been unable to take Barack Obama's outstretched hand.”
The leaders of Germany's Green party, Claudia Roth and Cem Özdemir, said the prize raised expectations that Obama would stick to his goals of peace, disarmament and fighting global warming.
The Norwegian Nobel Committee said it had attached “special importance to Obama's vision of and work for a world without nuclear weapons” in deciding to give him the prize this year.
“Obama has as president created a new climate in international politics,” the committee said in a statement released on Friday, highlighting the US leader's emphasis on multilateral diplomacy and the role of the United Nations.
“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.”