Private bank and asset manager the Edmond de Rothschild Group said on Thursday it would press ahead with legal action against a rival branch of the banking dynasty over use of the Rothschild name.

Shareholders in the rival business, whose holding company is known as Paris Orleans, voted on Thursday to change that name to Rothschild & Co with immediate effect.

The Edmond de Rothschild Group, which began the legal action a few months ago, said the name change would create confusion.

"We deplore this decision, which is tantamount to appropriating the use of the Rothschild family name, without any distinguishing element, and adds to confusion between the groups," the Edmond de Rothschild Group said in a statement.

Paris Orleans, the parent company of the Rothschild Group investment banking and asset management business, had announced plans to change its name in April. It said at the time the change was to better reflect the presence of long-term shareholders as well as their partnership culture.

The British and French parts of the Rothschild investment banking business were brought together under the Paris Orleans umbrella holding company in 2012. The Rothschild investment bank frequently ranks as a top 10 mergers and acquisitions adviser in Europe.

The Edmond de Rothschild Group has a 7.8 percent stake in Paris Orleans.