Alex Lubar, chief executive of McCann London, has been promoted to president of McCann Worldgroup Asia-Pacific.
He will take over from Charles Cadell, who is stepping down by the end of the year.
A statement from McCann said: "It should be no surprise that McCann Worldgroup always looks for career opportunities for our best people and when Charles Cadell approached [McCann Worldgroup chairman and chief executive] Harris Diamond about the idea of transitioning from his regional role over the next year, Alex Lubar was the obvious choice. He will be relocating to the region before the end of the year."
A spokesperson for McCann in Tokyo, where Cadell is based, said the company was not able to say any more at this time.
Cadell is among the most experienced agency leaders in Asia-Pacific. He has been with McCann in the region for the past eight years, initially based in Singapore as Southeast Asia and Australasia head, before becoming Asia-Pacific president in 2012 and then relocating to Tokyo in 2016 to also lead McCann Japan.
Before that, Cadell was chief executive of Lowe Lintas in India for three years and also spent 11 years at Leo Burnett in Malaysia, Hong Kong and Thailand.
Lubar has spent three years leading McCann London, after moving from the role of McCann global chief marketing officer. He previously worked at Grey and Bartle Bogle Hegarty.