UEFA's chief of women's football, Nadine Kessler, has warned of the damage the creation of a women's European Super League could have on the women's game.
Liverpool, Manchester United, Manchester City, Chelsea, Arsenal and Tottenham are part of a 12-club proposal for a new midweek men's competition which could effectively lead to a 'closed shop' for the clubs.
That has prompted a furious response from many quarters within the game, with the European Super League also planning a corresponding women's league which it claims will help "to advance and develop the women's game".
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However, Kessler, a former Germany international and World Player of the Year, dismissed the claims in a letter published on Twitter, saying: "It is a direct threat to all the plans we have carefully crafted, together with ECA (European Club Association), your clubs and the leagues, for (a) new UEFA Women's Champions League.
"Clubs need to be able to have the ambition of being part of the top of European women's club football, the UEFA Women's Champions League. With a closed European Women's Super League, this is not possible.
"Of course, such [a] development would be equally devastating for the national leagues, who have made enormous efforts to professionalise the women's game. All the great steps made in recent years… will have less of a chance of becoming a reality."
Sanderson: ESL won't derail women's game progress
Former Arsenal and Chelsea midfielder Lianne Sanderson remains upbeat on the future of the women's game despite the potential for big changes to investment levels across the sport with the proposed ESL.
"You can't compare the women's game to the men's because they are two completely different entities," Sanderson exclusively told Sky Sports News.
"If you look at the likes of Lyon and Wolfsburg in the Champions League they've more or less run away with the competition for years.
"We've already seen with the women's game the more money invested there are teams that are already breaking away in the league.
"It's already become a super league within the WSL because you have the links of Manchester City, Arsenal, Chelsea and Manchester United that are more superior to the other teams based on the money.
"But we're coming up to a really encouraging time, Sky Sports has obviously picked up the rights to the WSL which is so exciting and is still going to go ahead so I am still excited."
Sanderson: ESL timing is wrong, who do these clubs think they are?
Sanderson started her career at Arsenal before playing for both Chelsea and Juventus and she is disappointed with how her former sides have behaved over the European Super League proposals.
"I spent 12 years at Arsenal, I'm a Manchester United fan and also spent two years at Juventus so I am very disappointed at how the clubs I used to play for have handled this," Sanderson added.
"It seems like money talks and ironically the so-called 'Big Six' are not even in the top six in the Premier League so I don't know who some of these clubs think they are.
"It's so disappointing to say the least because football has really helped people during this global pandemic.
"The timing is everything and during a global pandemic, there's already enough negativity in the world without having to deal with this in the beautiful game.
"It makes me sad and the fans deserve to have a voice - we're all in agreement as to how we feel about this - it's a disgrace.
"I hope it doesn't happen and I do think there needs to be some form of punishment - a lot of the players' hands may be tied to a certain degree but I encourage them to speak out.
"I don't think it's a case of divide and conquer if they do speak out as well as pundits and fans as we all have a voice - it's about everyone speaking out because we're all in agreement here."
In a special podcast, Jasper Taylor sums up a seismic 24 hours in football after Arsenal, Chelsea, Liverpool, Manchester City, Manchester United, and Tottenham agreed to join a breakaway European Super League, along with six other teams.
The reaction has been swift, damning, passionate and emotional to say the least. Hear from Gary Neville, Kaveh Solhekol, Bryan Swanson and more...
Sky Sports has announced a three-year deal with the FA to become the primary broadcaster of the Barclays Women's Super League from September 2021.
As one of the most competitive leagues, with some of the most famous names and teams in the world, the WSL will be one of Sky Sports' flagship offerings.
The deal will see Sky Sports show at least 35 games exclusively live per season and further strengthens the broadcaster's commitment to women's sport.