Sadoun said new holding company 'will require every leader to be focused internally on integration'.
Brian Vella, managing partner in APAC, is now chief executive of the region.
'Think about the media environment we want in the future and how we are going to fund it,' Campaign Live audience told.
The Publicis Groupe CEO spoke publicly in the UK for the first time in six years at the Campaign Live conference.
Publicis has taken over five out of six markets pitched in Southeast Asia, with only Indonesia remaining with WPP's Mindshare.
Asahi Europe and International is reviewing its agency requirements outside Japan.
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