Japan's super-long-dated government bonds fell on Wednesday, steepening the ‍yield curve ‍across maturities, as investors sold those bonds ahead ​of a 30-year bond auction in the next session.

The 30-year ⁠JGB yield rose to a record high of 3.515% earlier in ⁠the session. ‌It was last up 2 basis points (bps) at 3.510%. The 20-year JGB yield also reached ⁠a record high, rising 2 bps to 3.1%. Bond prices move inversely to yields.

"The selloff is a natural move ahead of an auction, but ⁠in the current session, the ​market is selling off-the-run JGBs with maturities around 22 and 25 years, ‍as well as 14 and 15 years," said Tomoaki Shishido, a ​senior rates strategist at Nomura Securities.

"That is because investors sold low-coupon bonds to eliminate unrealised losses, as those losses can be covered by gains of equities."

Japan's Nikkei share average jumped 4% in the first two sessions of the year, notching a record closing high on Tuesday. The index was last down 1.12% as investors took profits from the ⁠rally.

The 10-year JGB yield fell ‌to a session low of 2.11% and was last flat at 2.120%. The five-year yield fell 1 bp ‌to 1.590%, ⁠while the two-year JGB yield fell 1.5 bps to 1.165%.

(Reporting ⁠by Junko Fujita; Editing by Subhranshu Sahu)