Struggling Russian automotive group AvtoVAZ (AVAZ.RS) plans to form a joint purchasing unit with its core shareholder Renault SA (RNO.FR) and Japan's Nissan Motor Co. (7201.FR) in a bid to reduce costs, a Renault spokesman said Friday.

Renault and Nissan have pooled their purchasing for many years as part of the Renault Nissan alliance that is cemented by cross-shareholdings. Renault owns 44.3% of Nissan while Nissan has a 15% interest in Renault.

A joint venture, Renault Nissan Purchasing Organisation (RNPO), is responsible for all of the duo's purchases.

Renault has a 25% shareholding in AvtoVAZ.

-By David Pearson, Dow Jones Newswires; +331 4017 1740, david.pearson@dowjones.com