TBWA Worldwide, the world's ninth-largest advertising agency network, will acquire a majority stake in Nippo Corp., a Japanese advertising agency affiliated with Nissan Motor Co., top executives of the three firms announced Wednesday.

TBWA is a subsidiary of Omnicom Group Inc., a communications marketing firm and the largest advertising organization in the world.

The move is seen by industry observers as yet another sign that foreign firms are expressing keen interest in entering various sectors of the Japanese market with the approach of wider deregulation.