BERLIN/FRANKFURT (Reuters) - The chief executive of General Motors' GM.N European arm Opel, Karl-Thomas Neumann, plans to resign as GM prepares to sell the business to France's PSA Group, German newspaper Frankfurter Allgemeine Sonntagszeitung (FAS) reported on Saturday.

FILE PHOTO - Dr Karl-Thomas Neumann, CEO of Opel Group speaks during a news conference on media day at the Paris auto show, in Paris, France, September 29, 2016. REUTERS/Benoit Tessier

Without citing its sources, the newspaper said that while Neumann sees the sale to PSA as the right strategic step, he is concerned that the new owner is underestimating the growing importance of electric cars.

Neumann planned to inform Opel’s supervisory board about his decision at its next meeting on June 22, the paper said in an excerpt of an article to be published on Sunday, made available to Reuters on Saturday.

Neumann wants to stay on board only until GM completes the sale of Opel to PSA Group, owner of the Peugeot, Citroen and DS brands, the newspaper added.

Opel declined to comment.

Opel this week said the sale, valued at 2.2 billion euros ($2.46 billion), could be completed as early as July 31, pending regulatory approval from antitrust authorities.

Neumann said in an interview in March he planned to remain in his job even under Peugeot, citing “great respect for each other”.

Neumann's mooted departure from Opel comes as the position of a top executive at Neumann's former employer, Volkswagen Group VOWG_p.DE, has been called into question in the wake of a scandal over rigged emissions tests.

The embattled chief executive of VW’s Audi division, Rupert Stadler, only got a five-year contract extension last month because of an agreement among supervisory board members that he would not serve out his full term, two sources have told Reuters.

Opel’s Neumann in 2013 joined GM to lead the U.S. carmaker’s European operations, which include the Vauxhall brand, after losing out in a management reshuffle at Volkswagen.

($1 = 0.8935 euros)