The world's leading players have written to the four Grand Slam tournaments calling for an increased share of revenue.
As first reported by French newspaper l'Equipe, the top 20 players from the men's and women's tour have sent a letter to the organisers of the Australian Open, French Open, Wimbledon and US Open.
The slice of the pie given out in prize money has been a consistent gripe of the players' despite sizeable increases in recent years.
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Last year the singles champions at Wimbledon took home £2.7m each while the overall pot was £50m, double what the All England Club awarded in 2014.
But overall revenues have also increased and players frequently cite comparisons to other sports, particularly basketball's NBA, to show they are missing out.
Explaining why she signed the letter, American Emma Navarro, ranked 11, told online outlet Bounces: "I talked a little bit to the other players about it and felt like it was a good idea to sign.
"And I think there have been some sort of unfair pay ratios - I don't know the correct terminology - in the past. And I think it's a good cause to come together as players and make sure we're getting treated fairly."
The news comes only two weeks after player body the Professional Tennis Players Association launched lawsuits in the United States, Europe and the United Kingdom against the ATP, WTA, International Tennis Federation and International Tennis Integrity Agency.
The PTPA, which was co-founded by Novak Djokovic, alleged "systemic abuse, anti-competitive practices, and a blatant disregard for player welfare".
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