The average yield on 2 billion pounds of 182-day bills maturing on Feb. 26, 2013, was 15.382 percent, up from 15.345 percent at last week's auction. The range of yields was 15.000-15.411.

On 1.5 billion pounds of 364-day bills sold, the average yield rose to 15.949 percent from 15.845 at the last auction weeks ago. The range of yields was 15.699-15.968.

The bank had originally sought 3.5 billion pounds in 364-day bills.

The central bank sells the bills on behalf of the Finance Ministry.