A tennis union co-founded by Novak Djokovic on Tuesday announced a series of legal actions aimed at the sport's governing bodies, alleging "anti-competitive restraints and abusive practices."

The Professional Tennis Players' Association (PTPA) said it was suing both tour organizers, the Association of Tennis Professionals (ATP) and the Women's Tennis Association (WTA).

The International Tennis Federation (ITF), and International Tennis Integrity Agency (ITIA) were also named as defendants in a series of actions in the United States, United Kingdom and the European Union.