By Eric Auchard and Laurence Frost

BERLIN/PARIS (Reuters) - BlaBlaCar, whose amateur chauffeurs share costs with passengers on long-distance journeys, will offer them cheaper car leases through French bank Societe Generale in the latest threat to traditional transport models.

The Paris-based start-up will first offer the new packages for Opel models through the bank's leasing business to more active BlaBlaCar drivers in France, before deploying the programme more widely, Chief Executive Nicolas Brusson said.

BlaBlaCar, whose phone app has some 40 million users in 22 countries, is among the so-called mobility services whose growth is disrupting carmakers and transport companies alike.

Besides ride-sharing, they include mainly local ride-hailing services such as Uber and car-sharing firms such as Avis-owned ZipCar, which offer access to self-drive vehicle fleets for as little as an hour at a time.

"The goal is to expand that geographically," Brusson said. "We can pioneer a new approach to car ownership based on usage."

In response to the threat, vehicle manufacturers and transport operators have struck deals with providers of mobility services over the past decade or developed their own.

Daimler launched car-sharing through its Car2Go subsidiary in 2008. Among many more recent deals, Opel parent General Motors invested $500 million in ride-hailing firm Lyft and PSA Group has backed several startups. Even France's state-owned SNCF railway has partnered with Zipcar.

DISRUPTIVE THREAT

BlaBlaCar allows car owners to cover their expenses but not make a profit - which shields it from regulatory costs and tax, further improving its appeal to passengers.

Thanks to its potential scale, the Societe Generale ALD Automotive partnership adds the competitive clout of corporate leasing to BlaBlaCar's already frugal peer-to-peer model. The start-up's 9 million drivers buy an estimated 1.3 million new cars each year.

Monthly rates would start as low as 164 euros including maintenance for the entry-level Opel Corsa mini, providing drivers complete at least one ride-sharing trip per month.

A four-year consumer leasing deal with a purchase option on a comparable Corsa would be about 227 euros per month, based on a quotation from Aramisauto, the online car retailer and price comparison service.

With clients typically paying 20 euros per journey, a driver could cover the entire vehicle leasing cost with just one round-trip per fortnight carrying two passengers.

"Ride-sharing is already an attractive option. Will it replace the ownership model? For most people no - but for some people, absolutely," Arndt Ellinghorst, a London-based analyst with Evercore ISI, said.

On larger models, the leasing plans will include on-board wireless internet for up to seven devices, a feature more often associated with higher-end ground transport services.

For ALD, Europe's biggest corporate leasing firm, the BlaBlaCar deal is a step into consumer car financing. The companies are also offering their ride-sharing plans on a handful of models from Toyota, Volkswagen and PSA's Peugeot.

(Additional reporting Edward Taylor in Frankfurt; Editing by Jane Merriman and Alexander Smith)