Daimler CEO Dieter Zetsche (left) listens as Renault-Nissan CEO Carlos Ghosn speaks during a press conference at the Paris auto show yesterday. The show opens to the public from today.

Daimler and Renault-Nissan are extending a manufacturing alliance, the two carmakers said yesterday, adding that there were no limits to how the co-operation could evolve.

“We maintain the attitude that everything is on the table. There are no sacred cows,” Renault chief Carlos Ghosn said at a news conference with Daimler Chief Executive Dieter Zetsche at the Paris auto show.

Both executives said projects under the alliance had ballooned from the three planned initially to 12 now and, according to Ghosn, were yielding significant cost savings in excess of €2bn ($2.5bn).

Mercedes, Nissan and Renault have shared engines, plants and vehicle underpinnings for small cars since Zetsche and Ghosn forged an alliance in 2010, cemented by token reciprocal shareholdings.

The pact is one of the few remaining alliances between a volume and a premium carmaker that has survived, in contrast to Daimler’s messy divorce with Chrysler and BMW’s sale of Rover.

The companies said the alliance was being extended to include engines, gearboxes and vans, including an agreement for Renault to supply Daimler with a 1.6 litre four cylinder diesel engine for use in its Mercedes-Benz C-Class.

Mercedes in turn will supply its 2 litre four cylinder gasoline engine and a 9-speed automatic transmission for use by Nissan’s premium brand Infiniti.

The companies said they had also struck a new cooperation deal on transporter vans. Nissan will supply Daimler’s Japanese commercial vehicles unit Mitsubishi Fuso Truck and Bus Corp (MFTBC) with a transporter van to be sold under the Fuso brand in key export markets.

Nissan’s NV350 van will be marketed as a Fuso Canter van in markets in the Middle East, starting this year.

Sharing development, procurement and even manufacturing costs helps both companies make savings, Ghosn said, adding that both companies measured the gains from the alliance each year by looking at things including goods, assembly and royalties.

“Based on projects underway and planned we expect annual revenue between the companies to more than double in the next six years,” Renault-Nissan chief Carlos Ghosn said, declining to elaborate on what the figure would be.

In June, Daimler and Nissan announced they would share costs to develop and build premium small cars, including building a production line with an annual capacity of 300,000 vehicles in Aguascalientes in central Mexico, where Nissan already has a $2bn manufacturing complex.

Projects between Renault, Nissan and Mercedes are assessed on a case-by-case basis, Ghosn said, adding there was no attempt to favour cooperation with any particular partner.

“Projects of the future are very balanced,” he said, adding that more companies could theoretically join the alliance.

Both companies had looked at extending a co-operation to include using the Mercedes Rear Wheel Architecture (MRA), but no feasible business case had been identified.

The level of co-operation between Mercedes, Infiniti and Renault-Nissan had matured and was no longer dependent on either of the chief executives for encouragement.

“If ever one of us would decide not to continue in his job, co-operation would continue,” Zetsche said.