UPDATE 2-VW to give union management seat to unlock reforms

* VW to replace HR chief at Friday board meeting -sources

* CEO-designate Diess to retain VW brand role -sources (Recasts, adds detail)

BERLIN/HAMBURG, April 11 (Reuters) - Volkswagen will hand labour leaders a management board seat as part of a broader pact to unlock structural reforms and win backing for Herbert Diess as new chief executive, sources said on Wednesday.

VW has considered listing its trucks business, creating a premium cars division and selling off motorbike brand Ducati, but such reforms attempted by CEO Matthias Mueller have been thwarted by turf wars and opposition from the company's labour leaders.

Europe's largest carmaker is poised to replace Mueller this week with VW brand chief Herbert Diess, seeking to inject fresh impetus to its recovery from an emissions scandal.

Diess is due to outline the group's new leadership structure in front of the supervisory board on Friday, two sources said.

"Diess will hold both positions, CEO of the company and the VW brand," a source familiar with the talks told Reuters on Wednesday.

This will hand Diess, hired from BMW in 2015, a sweeping mandate to review broader changes to the way VW's brands, which stretch from Skoda to Lamborghini, are managed.

To ensure Diess gets backing for his plans, Volkswagen's (VW) supervisory board will seek to replace personnel chief Karlheinz Blessing with a works council executive, Gunnar Kilian, who works directly under labour boss Bernd Osterloh, four sources close to VW told Reuters.

Kilian has already discussed his installation as personnel chief with Wolfgang Porsche, who "did not oppose" the plan, a person familiar with the deliberations said on Wednesday. Porsche is a member of VW's supervisory board and the head of the family clan which owns a controlling stake in VW.

VW and the works council declined comment. Kilian's appointment, first reported by German magazine Der Spiegel, would give VW's labour representatives a direct say on cost cutting and strategy debates at management board level.

Spiegel added that VW plans to split its business into four divisions -- a volume brand group including VW, Seat and Skoda, a premium brand group consisting of Bentley and Audi, a sportscar group including Porsche, Bugatti and Lamborghini and a commercial vehicle and trucks arm.

Removing Blessing and installing Kilian will be part of a broader reshuffle that could also affect other senior executives, another source said.

Senior works council members last year had their salaries cut and bonuses suspended after public prosecutors investigated alleged overpayments at the carmaker, a move that labour leaders are blaming on Blessing, one source said. (Reporting by Andreas Cremer, Jan Schwartz, Irene Preisinger and Ilona Wissenbach Writing by Edward Taylor Editing by Keith Weir)