But she said it was too early to declare victory, describing the 17-member bloc that shares the euro currency as an unfinished project that could not afford to rest on its laurels.
"I know that pushing through treaty changes in the member states can be difficult, but if you want more Europe, you have to be prepared to develop it further," Merkel said.
"In a world that is constantly changing, we can't stand there and say that at some point we agreed the Lisbon Treaty and there's no need to change it again. This won't work."
(Read more: Merkel III: Will the euro area be third time lucky?)
Germany wants closer coordination of economic policy to complement the bloc's single monetary policy and will push at a summit of EU leaders this week for members to agree binding contracts with the European Commission that would oblige them to take certain economic reform steps.
At the same time, it is pushing for changes to the Lisbon Treaty to allow for greater European control over policy, a move that is highly controversial in other members, including neighbor France, where Merkel will travel later on Wednesday to meet with French President Francois Hollande.