German carmaker BMW and larger rival Volkswagen announced surprise changes to top management on Tuesday, with the veteran CEO of the Munich-based luxury group stepping down a year early and handing the reins to the firm's younger production chief.

BMW said chief executive Norbert Reithofer, who has run the company since 2006, would step aside in May. Harald Krueger, a 49-year-old who has led BMW's push into emerging markets like China, will take his place, becoming one of the youngest executives ever to run a global carmaker.

In a related move, Volkswagen announced it had recruited BMW's research and development chief Herbert Diess to run its flagship VW passenger car brand.

One source told Reuters that Diess bolted to VW after failing to get assurances that he would succeed Reithofer, whose contract had been due to expire in 2016. When Diess left, BMW decided to accelerate its own succession plan.

The move turns Diess, a 56-year-old engineer, into a strong candidate to replace Winterkorn as CEO of Europe’s largest carmaker when his contract expires in 2016.

Investors have been seeking clarity on the succession plans at both carmakers. Winterkorn, who has run VW since 2007, is 67 years old.

Reithofer is 58, close to the regular 60-year-old retirement age for top executives at BMW.

He will become chairman of BMW’s supervisory board, a non-executive role that will nonetheless allow him to continue to exert influence over the group he joined over a quarter of a century ago. Reuters reported on Monday that BMW was on the verge of making changes to top management.

Krueger is seen as a conservative choice to run BMW. He was responsible for human resources and ran the Mini and Rolls-Royce brands, as well as BMW's motorcycle division and after-sales services before taking charge of production in 2013. – (Reuters)