Kuroda highlighted differences between the BOJ's climate approach and those of some European counterparts, saying it had no plans to hand-pick "green" bonds in its asset-buying programme
Yields on 20-year JGBs added half a basis point at 0.430% midway through the afternoon session, while 30-year bond yields gained 1 basis point at 0.685%.
Japan's economy shrank an annualised 3.9% in the first quarter and is seen making only a modest rebound, if any, in the current quarter after an extension of coronavirus emergency curbs for Tokyo and other major areas.