Matthias Mueller, VW's former head product strategist who joined the group's top management board in March, is favoured by a majority on VW's 20-member supervisory board, which will endorse him as new CEO at a meeting on Friday, the source said.

Winterkorn, an engineer by training who spent almost nine years at the helm of Europe's largest automaker, resigned on Wednesday, taking responsibility for the biggest business scandal in VW's 78-year history.

Mueller, 62, who held various positions at VW's luxury flagship Audi before taking charge of Porsche in 2010, was also the favourite candidate for VW's top job by long-time chairman Ferdinand Piech, who quit in April after a power struggle with Winterkorn.

Labour representatives, occupying half of the 20 board seats, would "only accept a personality with great technical and entrepreneurial expertise as well as great social competence," VW works council chief Bernd Osterloh said in a letter to employees published on Thursday.

VW declined to comment.

Mueller's appointment will be part of a raft of personnel decisions and dismissals by the board including the firing of R&D chiefs at Audi and Porsche, Ulrich Hackenberg and Wolfgang Hatz, as well as VW's top U.S. executive Michael Horn, a source told Reuters earlier on Thursday.

(Refiles to add full name, Matthias Mueller in second para)

(Reporting by Andreas Cremer; Editing by Kirsti Knolle and Mark Potter)

Valeurs citées dans l'article : Volkswagen AG, APRIL, Audi AG, GREAT