The G7 pledged to make a coordinated response to a slowdown in the global economy, but signalled no shift in policy and differed in emphasis on the euro zone debt crisis.

Adding to the euro zone's problems, the European Central Bank's chief economist Juergen Stark resigned unexpectedly on Friday, highlighting a conflict within the institution over its policy to buy government bonds.

Also, France's top banks were bracing for credit rating downgrades on worries over their Greek exposure, while senior German politicians have begun talking openly about a Greek default.

"The G7 was a bit of a non-event," one trader said. "The Greek situation is dominant, chances of some sort of default have increased -- the Germans seem to be hinting at that -- so risk is off."

The December Bund future was last 21 ticks higher at 137.98 after hitting a contract high at 138.28 immediately after the open. Ten-year German yields were down 1.4 basis points at 1.752 percent.

Uncertainty also remains about the Greek debt swap aimed at helping Greece secure a second bailout and giving it more time for reforms. Athens has said it will not go through with the debt swap unless the participation rate is 90 percent.

The EU's Economic and Monetary Affairs Commissioner Olli Rehn said the work for private sector contributions is proceeding well.

Greece introduced a new tax on real estate on Sunday in a bid to bring its 2011 budget back on track and meet the obligations of its bailout deal.