Reuters reports that Bank of Japan Deputy Governor Masayoshi Amamiya said the central bank must focus on keeping the entire yield curve "stably low" for the time being, as the economy continues to suffer from the coronavirus pandemic.

But he also said he personally felt bond yields should be allowed to move more around the BOJ's 0% target "as long as it does not diminish the impact of monetary easing".

"A big fluctuation in interest rates could have undesirable consequences. But when it's limited to a certain range, it's possible to enhance bond market functions, without diminishing the monetary easing effect of our policy," he said in a speech.

Amamiya said there was no change to the BOJ's view that excessive declines in super-long interest rates hurt margins of pension funds and insurers.

But he said the BOJ's near-term focus was to keep bond yields stably low, echoing comments made by Governor Haruhiko Kuroda on Friday