The German finance ministry is counting on Greece's debt buyback operation being successful as this is central to the euro zone's rescue efforts, a ministry spokeswoman said on Monday.

"A successful debt buyback is of course an integral part of the agreement of November 27 in the Eurogroup," said spokeswoman Marianne Kothe. "We are counting on a successful implementation of this part of the program and on this action being carried out successfully with a corresponding effect on debt levels."

(Reporting by Stephen Brown and Erik Kirschbaum)