Battered in recent months by the worst industry downturn since World War II, automakers heading to the International Auto Show in Frankfurt Monday are pinning their hopes on early signs that a slow market recovery might be gaining traction.

"We expect the (Frankfurt show) to be a positive trigger for the auto sector," said Commerzbank analyst Daniel Schwarz. "This follows a frustrating Paris Motor Show in 2008, and a Geneva auto show (in March) where it was unclear whether markets had already hit the bottom, but vague hope that government incentive schemes would provide some relief."

Schwarz added that premium automakers, in particular, were expected to provide a more upbeat tone in Frankfurt.

Some analysts cautioned, however, that markets were suffering from distorted dynamics following government-backed scrapping incentives in many countries, with some manufacturers benefiting from state aid to weather the storm.

Premium automakers received little support from these scrapping incentives, which were rolled out in several major markets to revive demand for new cars after sales came to a grinding halt amid the economic downturn.

Analysts believe that BMW AG (BMW.XE) and Daimler AG's (DAI) core Mercedes-Benz brand, the world's two largest luxury automakers by sales, will be affected less by a downturn in sales once these scrapping incentives expired.

"BMW is a high quality way to gain exposure to the potential we see for positive U.S. market surprises," said Morgan Stanley analyst Adam Jonas in a note to clients, when he upgraded the stock to overweight on Tuesday.

BMW was hit hard by the U.S. market downturn as this was the company's largest single market until recently. The magnitude of any impact from the withdrawal of incentives, which mainly will affect mass-market manufacturers such as Volkswagen AG (VOW.XE) and Fiat SpA (F.MI), is expected to be in the spotlight during the Frankfurt show, along with the latest trends in alternative drivetrains and electric cars and plans for new alliances between companies to share costs.

Driven by investments as part of several economic stimulus packages around the globe, automakers have been ramping up efforts in the field of green technologies, such as hydrogen-powered vehicles or plug-in electric cars, despite some persistent technological and financial obstacles.

Mercedes-Benz will exhibit a fuel-cell version of its compact B-Class, powered by hydrogen. Toyota Motor Corp. (7203.TO) is presenting an electric plug-in version of its Prius model. Its Japanese rivals Honda Motor Co. (7267.TO), Nissan Motor Co. (7201.TO) and Mitsubishi Motors Corp. (7211.TO) won't be present at the show as they seek to cut costs.

The stand of General Motors Co.'s European Opel brand is set to attract visitors' attention in Frankfurt as the company, headquartered nearby in Ruesselsheim, presents the new-generation of its best-selling Astra model just days after the sale of the unit to Magna International Inc. (MGA) was clinched Thursday.

The success of the Astra is crucial to help Opel and its British sister brand Vauxhall through the looming restructuring.

French automaker Renault SA (RNO.FR) is presenting a new version of the Megan along with several electric concept vehicles. French peer PSA Peugeot Citroen (UG.FR) is focusing on two new small cars, the DS3 and the C3, as well as the sleek Peugeot RCZ sports car.

Italian automaker Fiat SpA (F.MI) is presenting the revamped Punto model as well as a cabrio version of its 500 model, while the new-generation C-Max will be in spotlight at Ford Motor Co. (F).

-By Christoph Rauwald, Dow Jones Newswires; +49 69 29 725 512; christoph.rauwald@dowjones.com