Germany's debt agency has said that an auction of the country's benchmark 10-year bonds did not receive sufficient bids.
It said this was due to a "very volatile market environment" and as investors balked at the record-low yields.
The agency stressed there is no danger for the financing of the federal budget.
Germany's central bank said the auction of €5 billion only received bids worth €4 billion. The agency €3.2 billion in bonds at an average yield of 1.52%.
It said it will keep the remaining €1.8 billion for sale later on secondary markets.
The debt of Germany is viewed as a safe haven amid the euro zone's debt crisis. Its popularity, however, has caused the yield to drop sharply, making it less attractive for traders seeking not just safe investments but good returns.
