Manulife (MFC.TO), Canada's biggest insurer, said on Tuesday that it planned to promote the head of its Asian business, Philip Witherington, to be chief financial officer from the start of 2018.

He will succeed the current CFO, Steve Roder, who had decided to retire at the end of 2017, the company said.

The move is among senior management changes that are part of a restructuring by incoming chief executive Roy Gori, who takes up his new role on Oct. 1.

Manulife said it had appointed Paul Lorentz, who has previously held senior roles in its wealth and insurance businesses, as head of its global wealth and asset management business. He will take up his new position in October.

The insurer also appointed Naveed Irshad as head of its North America Legacy Business.

Irshad, who is currently the CEO of Manulife Singapore, will take up his new role in January.

In a statement, Gori said the appointments "showcase the bench strength of Manulife's senior leadership team, and position us strongly as we accelerate our transformation."