The benchmark 10-year JGB yield added half a basis point (bp) to minus 0.055 percent, while December 10-year futures were down 0.13 point at 151.69 in afternoon trading.

Prices in the superlong zone were steady, with the 20-year JGB yield flat at 0.380 percent and the 30-year yield also unchanged at 0.495 percent.

The 2-year yield and the 5-year yield both rose 2 bps to minus 0.240 percent and minus 0.185 percent respectively.

The Bank of Japan refrained from offering to buy JGBs under its asset purchase programme on Monday.

On Tuesday, the Ministry of Finance will auction 1.1 trillion yen ($10.59 billion) of 20 year JGBs, followed by a sale of 2-year notes on Thursday.

Data issued early on Monday showed Japan's trade balance at a surplus of 498.3 billion yen ($4.8 billion), versus the median estimate of a 341.8 billion yen surplus.

But the yen's recent relative strength took a toll on exports, which fell for a 12th straight month.