"We are doing what the finance ministers did in Luxembourg yesterday and what Chancellor Angela Merkel did recently, we are calling on them in other words to support the Papandreou government in the very responsible and very difficult line it is following for the country," he said.
Seiffert said the German government considered the approval of the new measures by the Greek Parliament a necessary condition for extending further aid to Greece.
German finance ministry spokesman Martin Kreienbaum said the Greek Parliament had to make clear whether the measures would be approved and how they would be implemented.
"The next move must be made by Greece. It must show that it is in a position to approve and carry out these measures on a national level," he said.
He noted that Greece would need money by mid-July, by which time decisions concerning the next tranche of aid to Greece will have been made.