The economic crisis will trigger a big cut in the number of global automakers, Fiat group CEO Sergio Marchionne said.

Marchionne thinks there could be only six survivors in the global volume sector as falling new-car sales and rising financial losses lead to a wave of consolidation in the industry.

"By the time we finish with this in the next 24 months, as far as mass-producers are concerned, we're going to end up with one American house, one German of size; one French-Japanese, maybe with an extension in the US; one in Japan; one in China and one potential European player," Marchionne said.

"The only way for companies to survive is if they make more than

5.5 million cars per year," Marchionne told Automotive News Europe.

At present, only five automakers -- Toyota, General Motors, Volkswagen, Ford Motor and Renault-Nissan -- have that kind of scale.

Marchionne said: "This business is going to be completely different. It cannot continue as it did in the past. Independence in this business is no longer sustainable."

Analysts think bigger companies are likely to be the ones best placed to achieve cost savings and spread the expense of research and development in the future.

This could mean the end of some famous and long-established brands.

The main reason there are so many automakers in Europe is because many are family owned, said Jürgen Pieper, analyst at Metzler Bank in Germany. But this might change in a prolonged financial crisis, he added.

Size matters

For example, companies such as BMW, which is 46.6 percent owned by the Quandt family, and PSA/Peugeot-Citroen, 30 percent owned by the Peugeot family, could be put up for sale if their fortunes decline.

In Europe, PSA, BMW and Fiat are seen as most vulnerable if the downturn accelerates. That is because they are not big enough to enjoy the economies of scale of their rivals.

Pieper expects VW, Renault-Nissan and Daimler to survive.

"Size in the current situation is what matters," he said.

Scale makes it cheaper to buy parts and also spreads the cost of research and development across many models and a greater number of cars.

"Audi has been doing better than Mercedes and BMW over the last few years because it benefits from being owned by VW," Pieper said.

These factors are key reasons behind Porsche's decision to buy VW.

And there may be more mergers and acquisitions, as automakers look to create sustainable structures.

Buyouts could likely come in two forms, said Max Warburton, an analyst at Sanford Bernstein. On one side, volume carmakers could come together to cut their losses. On the other, German premium carmakers could, despite bad experiences in the past, look at buying volume carmakers again to grow in size.

"We believe that any or all of Fiat Auto, Peugeot, Renault, Ford Europe and GM Europe could potentially be involved in m&a," Warburton wrote in a recent report.

But some analysts don't believe m&a is going to be the solution to the problems the industry faces today.

"In a recession I do not think there will be much consolidation," said Garel Rhys, emeritus professor of motor industry economics at Cardiff Business School in Wales. "I cannot see anyone wanting to get into bed with anyone else."

Rhys said the car companies have too many problems of their own to look into merging with rivals.

He also questioned the logic of two companies in trouble pooling resources. "Two drowning men do not make a good swimmer," he said.

Even if big European carmakers would decide a merger or takeover is their best option, they could be stopped by EU competition rules. If VW bought Fiat, for example, the combined company would have more than 30 percent of the European market.

Already scarred

The European Commission must be notified when a planned merger or takeover would create a group with global revenue of more than

€5 billion and at least two of the companies have revenues of at least €250 million in the EU.

The Commission would investigate whether the takeover reduced competition and consumer choice while boosting prices, an EU spokesman said.

Daimler has been scarred by its experience with Chrysler, BMW bought Rover but sold it again after high investments failed to pay off.

Analysts say both episodes showed that synergies between premium and volume carmakers are elusive.