F Ford Motor Company

MILAN—Fiat Chrysler Automobiles NV's Harald Wester had stepped down as the head of Alfa Romeo and Maserati, the latest sign of how the automotive group is struggling to fire up its two premium brands.

Reid Bigland, the head of Fiat Chrysler's sales in the U.S. and its Canadian operations, will take over as chief executive of Alfa Romeo and Maserati whose recent performance has included delays in product launches and disappointing financial results.

While Mr. Wester is still part of Fiat Chrysler's group executive council and keeps his position as Fiat Chrysler's chief technology officer, losing the more hands-on role of running two of the group's brands likely marks the end of his ascendancy within the group.

Fiat Chrysler didn't make either executive available for comment.

Alfa Romeo has struggled in recent years and Fiat Chrysler's much touted relaunch of the brand that kicked off a year ago has stalled. The brand has failed to make significant inroads against stiff German competition. In June 2015, Fiat Chrysler presented the Giulia sedan, the first product to come from what was supposed to be a 5-billion-euro, five-year plan presented a year earlier.

Fiat Chrysler has since dialed back investments originally intended for Alfa Romeo so they could be directed to expanding other brands in the group's portfolio. Alfa Romeo has pulled back from ambitious sales targets in China and a much-touted return to the U.S. market, originally intended for 2012 after a 20-year absence, has failed to take shape.

Maserati has also been unable to meet the ambitious forecasts set by Fiat Chrysler CEO Sergio Marchionne. The brand's expansion is pinned to the release of the Levante crossover, the luxury brand's first dip into the rapidly expanding segment. Maserati sales declined 13% last year, as operating profit collapsed by almost two-thirds.

The Levante hit European showrooms this month and will be available in the rest of the world by year-end. The launch is a year behind schedule and comes a decade after the presentation of the crossover as a concept car.

Mr. Bigland has overseen more than six years of Fiat Chrysler sales growth in the U.S. In Canada, he helped the company become the top seller in 2015, the first time it has managed to edge out Ford Motor Co. and General Motors Co.

"It is time now for our efforts to be directed toward the global commercial expansion of these two brands [Alfa Romeo and Maserati], and I can think of no one better than Reid to fulfill that mission," Mr. Marchionne said in a statement

While the promotion puts Mr. Bigland more in the spotlight, he is taking over two brands that, while important for Fiat Chrysler's reputation, remain marginal when the company is concentrating its efforts on expanding the more mass-market Jeep and Ram brands. Mr. Marchionne recently said he expects the shift in consumer tastes in the U.S. toward sport-utility vehicles and trucks to be permanent.

To save money it can invest elsewhere, Fiat Chrysler, the only indebted global car maker, plans to outsource the production of its Dodge Dart and Chrysler 200. Inventory of the two sedans has been accumulating in recent months and in April the company began offering deep discounts and favorable financing to move the cars off dealer lots. Sales of both models have plunged in recent months.

Write to Eric Sylvers at eric.sylvers@wsj.com

(END) Dow Jones Newswires

May 24, 2016 08:15 ET (12:15 GMT)

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