Mitsubishi UFJ decided on the postponement taking into account investor appetite and market conditions, the spokesperson said. He declined to comment on the planned issue amount.

Sources have said Mitsubishi UFJ and Sumitomo Mitsui Financial Group Inc, may put April issuance on hold amid the volatility.

AT1 bonds - a $275 billion sector known as "contingent convertibles" or "CoCo" bonds - can be converted into equity or written off if a bank's capital level falls below a certain threshold.

As part of the rescue of Credit Suisse by its rival UBS, Swiss regulator FINMA determined that Credit Suisse's AT1 bonds with a notional value of 16 billion francs ($17.35 billion) would be wiped out, a decision that stunned global credit markets and angered many holders.

(Reporting by Ritsuko Shimizu and Makiko Yamazaki; Editing by Varun H K)