New Delhi, March 18 -- HDFC Bank on Wednesday said its chairman Atanu Chakraborty has resigned with immediate effect, with his letter from 17 March to the board citing "certain happenings and practices within the bank" that were "not in congruence" with his personal values and ethics.

In a late-night announcement, India's largest private sector lender said the Reserve Bank of India (RBI) on Wednesday approved the appointment of board member and HDFC group veteran Keki Mistry as an interim part-time chairman for three months from 19 March.

"We confirm that there are no reasons other than those mentioned in the said letter, for the resignation of Chakraborty," the bank said.

Chakraborty, who had joined the board of HDFC Bank in May 2021,...