UPDATE 1-Internal favorite Mark Read to be appointed new WPP CEO-source

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LONDON, Aug 30 (Reuters) - WPP is set to name Mark Read as its new chief executive as early as next week, opting for the leading internal candidate to replace Martin Sorrell at the world's biggest advertising company, a city source told Reuters.

Read, the unassuming former digital boss of WPP, stepped up to become joint chief operating officer of the company after Sorrell, its founder, quit in April after 33 years in charge following a complaint of personal misconduct which he denied.

Due to publish results next Tuesday, WPP declined to comment.

The city source, who declined to be named because the decision is not yet public, said Read was set to be named as the new boss as early as next week as long as the two sides have agreed terms.

He takes over the 16 billion pound company at a difficult time, as the industry goes through a period of unprecedented change as clients seek to save costs by doing some digital marketing themselves and others turn to consultants for advertising advice.

Others are placing ads directly on Google and Facebook.

Read told Reuters in June that WPP needed radical change to stay ahead of the digital revolution reshaping the industry.

News of Read's appointment was first published by the Financial Times. (Reporting by Kate Holton; Editing by Kirsten Donovan)