The Bank of New York Mellon Corp., the country's sixth-largest bank with more than $1.3 trillion in assets under management, said late Wednesday that Robert Kelly has stepped down as chairman and chief executive officer due to differences with the bank’s directors regarding his management approach.

Gerald Hassell, president and board member has been named as Kelly’s immediate successor. Hassell, 59, has been with the former Bank of New York for more than three decades while Kelly led the bank since 2007. Kelly served as chief executive officer of Mellon Financial Corp. prior to the merger of Bank of New York and Mellon Financial.

In a statement, BNY Mellon did not elaborate on Kelly’s resignation. “Gerald is ideally positioned to guide BNY Mellon through the next phase of its growth and to bring it to its full potential,” said Wesley van Schack, lead director of BNY Mellon.

BNY Mellon, created after the $16 billion merger of Bank of New York and Mellon Financial in 2007, has more than $26 billion in assets under custody and administration and more than $1.3 trillion in assets under management.

On Aug. 10, BNY Mellon said it planned to cut 1,500 jobs or 3 percent of its workforce, after operating expenses soared in the second quarter. BNY Mellon shares have lost almost one-third of their value so far this year, closing off 15 cents a share at $20.67 ahead of the surprise announcement before trimming another 33 cents a share in after-hours trading.

For more details and reaction to the unexpected departure of BNY Mellon CEO Robert Kelly, feel free to click on the following links:

What’s Next for BNY Mellon’s Wealth Management Unit Following Kelly Exodus?

New BNY Mellow Leadership Could Signal Strategy Shift