General Motors' Opel unit and PSA Peugeot Citroen are still talking joint vehicle development but won't build cars together for now, the German brand's interim chief executive has said.

"The quality of the talks is really very good. And the operational and technical advantages are so great that we will surely will be able to wrap up soon the negotiations on joint vehicle development," Thomas Sedran told WirtschaftsWoche, according to Reuters.

The plan is to come up with four new model lines by 2016/2017: a successor for the Opel Zafira MPV [minivan] the current plant for which is now confirmed doomed, two compact cars and a successor to the mid-sized Opel Insignia and Citroen C5.

Reuters noted that GM and Peugeot unveiled an initial alliance agreement in February with the goal of saving at least US$2bn annually within five years, evenly split between the partners.

GM paid EUR320m ($419m) for a 7% stake in Peugeot as part of the original deal.

People close to the situation told Reuters last month that the partners had halted talks on an even deeper tie-up amid misgivings about the French carmaker's worsening finances and government-backed bailout.

Opel aims to boost business in Russia and Turkey by capitalising on its German brand, Sedran also told Wirtschaftswoche.

It was working on a plan to boost Opel sales in China from 5,000 units a year now. "You can only be successful in China if you produce there. Plants in Europe aren't much help."

Some Opel models are already built and sold in China other under brand names such as Buick - one version of the Excelle is essentially the current Opel Astra.