It was the first time the conservative Chancellor has questioned Germany's pledge to phase out the country's 17 nuclear power plants since she became head of a coalition government of conservative Christian Democrats and Social Democrats in 2005.
The anti-nuclear policy was agreed by former chancellor Gerhard Schroder's coalition of Social Democrats and Greens in 2000 and has been a key element in Germany's drive to develop alternative energy sources. The policy has been dismissed by the nuclear lobby and conservatives as "pure ideology".
Social Democrats tried recently to quash any notion that Germany plans to end its anti-nuclear stance. Ulrich Kleiber, the SPD deputy parliamentary leader, said: "Somebody who uses oil supply bottlenecks as an argument in favour of nuclear energy isn't capable of grasping the issue."