The Premier League will launch a legal challenge to Ofcom's ruling forcing Sky to cut the price it charges rival broadcasters to carry their sports channels.
The challenge to the Competition Appeals Tribunal was confirmed following a meeting of top-flight clubs' chairmen today.
Premier League chief executive Richard Scudamore said: "We have concluded that we have no option other than to mount a challenge to their proposed action.
"We do not undertake this process lightly. However, the consequences for UK sport and UK sports fans are too serious and fundamental for us to ignore."
The league fear the ruling will lead to a drop in their clubs' income with the effect of that being the world's top players turning their back on England's top flight.
Sky will have to sell on Sky Sports 1 and 2 to rival broadcasters for up to 23% less than the current wholesale price, according to the ruling by the regulator.
The Premier League, who have just signed a three-year £1.782billion broadcast deal with Sky paying £1.62billion of that, have studied the 635-page Ofcom decision in detail.
Scudamore added: "By forcing Sky to sell its sports channels to its competitors at a discount, Ofcom will reduce the incentives of all broadcasters, Sky included, to invest in the acquisition of sports rights.
"This can only have a negative impact on the ability of sport to attract a fair return on its content in an open market, which is necessary to ensure appropriate investment in maintaining the highest quality of that content.
"The effect will be to subsidise companies that have shown little appetite for investing in content and fundamentally damage the investment models that have helped sport become a successful part of the UK economy and made sport so attractive to UK consumers."
Scudamore said it was vital for there to be competition for Premier League broadcast rights.
He added: "We want to see competition for our content; it attracts value to invest in what fans want - playing talent and facilities - anything that diminishes that investment will be bad for the game and bad for sports fans as a whole.
"This is why it is critical for the Premier League to defend its ability to provide the quality football that has underpinned the successful development of the English game.
"We, and our clubs, operate in a highly competitive market and we intend to resist strenuously this unjustified attempt to reward risk-averse companies and undermine not only English football but UK sport as a whole."
An Ofcom spokesman said: "It is in consumers' interests for our pay TV decisions to come into effect as soon as possible to deliver the benefits of wider choice and innovation. We are happy to defend our decision wherever necessary."Reuse content