DBS said yesterday in a statement that Mr Wong will step down as the group's chief operating officer and DBS Bank's vice-chairman, as well as from the boards of the group, DBS Bank (Hong Kong) and DBS China on Aug 31.

Mr Wong, 60, had planned to retire by the end of this year but decided to bring this forward.

DBS chief executive Richard Stanley will take over all his positions.

'Frank's direct reports will report directly to Richard,' said Mr Koh Boon Hwee, the DBS chairman, in an internal e-mail message to staff.

This will give Mr Stanley, a former Citibanker who joined DBS on May 1, oversight of the bank's consumer, enterprise, corporate, investment banking and global financial markets divisions.

Mr Stanley, who previously headed Citi's China business, will also be directly in charge of the teams driving DBS' expansion in Greater China and Hong Kong.

An analyst with a foreign bank said: 'This arrangement makes a lot of sense, since Mr Stanley can leverage on his years of experience in China to drive DBS' growth in the Taiwan-China-Hong Kong triangle.'

He added: 'It is also significant that Richard has the key profit centres of the group reporting straight to him, unlike his predecessor Jackson Tai.'

Mr Koh told staff in his e-mail message that Mr Wong had been persuaded to defer his retirement plans 'time and again' since early 2006.

But with Mr Stanley on board since May 1, and the 'management transition progressing smoothly', Mr Wong had recently broached the matter again, Mr Koh said.

'He felt we now have a strong team in place to take the bank to the next level... I reluctantly accepted Frank's request,' he added.

Mr Koh said DBS is 'well- placed with the strong team and legacy that Frank has built', and praised him as being 'instrumental in DBS' journey to transform itself into a leading bank in Asia'.

To ensure a smooth handover, Mr Wong will 'focus solely on managing the transition of our senior client relationships to Richard and other senior managers', he added.