Renault and Nissan could be preparing to cement their relationship with a merger that would see the French and Japanese car manufacturers form a single corporation, reports have claimed.

Renault’s share prices jumped 5.4% at the opening of today’s trading as a result of the speculation which could realise cost savings in research and development, parts supply and manufacturing in an industry where “size matters”.

Sources of news outlet Bloomberg claim that the brands will end their two-decade-old alliance under a single stock as part of the move, which is understood to be driven by Renault's chairman and chief executive, Carlos Ghosn (pictured).

Spokespeople from Renault-Nissan have so far refused to comment on what was referred to as “speculation”.

Renault currently owns 43% of Nissan while the Japanese carmaker has a 15% stake in its French counterpart.

Janet Lewis, an analyst at Macquarie in Tokyo, told Bloomberg: “Size matters in the auto industry.

“The concern has always primarily been the French government, and somewhat Japan, because both France and Japan like to keep their national champions.”

The French government currently owns 15% of Renault and may be reluctant to see the merger take place.