Nissan Motor Co. said Friday that it has failed to reach an agreement on the purchase of additional stakes in its two units in Thailand due to differences over the selection of the firms' management.

The failure of the negotiations with Siam Nissan Automobiles Co. and Siam Motors & Nissan Co., however, will not affect its overall operations in Thailand, the Japanese automaker said.

Nissan reached a basic agreement with the two firms in March over its additional investment, which would have raised its stakes in each firm from 25 percent to 74.9 percent, a move intended to strengthen its presence in Southeast Asia.

Some 41,000 Nissan cars were produced by the two Thai firms last year.