Japan's Nissan Motor Co (7201.T) and France-based Renault SA (RENA.PA) plan to use common parts in the production of new versions of the Nissan March and Renault Clio to reduce costs by about 30 percent, the Nikkei said.
The common parts in the two models, expected to roll out in 2015, are likely to constitute about half of the total parts used, the Japanese daily said.
The companies will gradually extend this unified format - currently focused on about 3 million small automobiles a year - to other models, the paper said.
Company officials are meeting to finalize a strategy for using the common parts from the design stage, the daily said.
Nissan and Renault, which have partnered since 1999, have been exploring the idea of a unified design for midsize automobiles for four years, the Nikkei said.
(Reporting By Pallavi Ail in Bangalore; Editing by Maju Samuel)