'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.
McCann London leads McCann Worldgroup to victory in four-way pitch.
Clerke will move from Cape Town to London to take up the role.
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