The Federal Trade Commission has filed a request to halt the integration of Wild Oats into the activities of Whole Foods Market as part of the ongoing legal battle over the upmarket retailer's 2007 acquisition of its smaller rival.

The FTC has attempted to block the merger of the natural and organic retailers, claiming that it reduces competition in the market.

The FTC also indicated that, if the US Court for the District of Columbia - the court hearing the case - finds in its favour, it would seek to rebrand the acquired stores as Wild Oats and establish a separate management structure.

"The FTC believes that this preliminary injunctive relief is necessary and reasonable to preserve interim competition and maintain the commission's ability to fashion an effective remedy should it be warranted," the FTC said in its filing.