Novak Djokovic calls for a players' union to demand greater prize money

Novak Djokovic has earned almost $110m (£80m) in his career

Novak Djokovic has called for male professional players to form a union and demand greater prize money at ATP tournaments and Grand Slams.

The 12-time Grand Slam champion made the announcement at the compulsory annual players' meeting at the Australian Open in Melbourne.

According to the Daily Mail, the Serbian asked ATP officials to leave the room before addressing the players.

Djokovic, 30, has earned almost $110m (£80m) in his career.

But he believes players are still not being paid enough compared with other successful sports stars.

Roger Federer, Andy Murray and Rafael Nadal were among the players in attendance.

'There could be major repercussions'

BBC tennis correspondent Russell Fuller

Some players feel they deserve a larger slice of the cake, and may point to the tens of millions of pounds in profit generated by Wimbledon every year.

The rewards at the very top level are astronomically high: Djokovic, Federer and Nadal have won more than $300m (£217m) in prize money between them. And yet, if you are are outside the top 100, it can be a struggle to earn a decent living. Lower ranked golfers are comparatively better rewarded.

Part of the subtext to this is that a significant number of male players still do not believe in equal prize money. Djokovic himself said at Indian Wells in 2016 that men currently deserve higher prize money because "the stats are showing we have much more spectators".

The stats for men's tennis may not look so promising five years from now, but if the push for a separate player's union gathers momentum there could be major repercussions for the sport.