A UEFA report has shown that nine European clubs have moved so far ahead of the rest financially that they are unlikely to be caught up with.
The organisation's European Club Footballing Landscape report, released on Thursday, said five of the "super clubs" are in the Premier League -- Manchester United, Manchester City, Arsenal, Chelsea and Liverpool.
It revealed that the total wage bill in the Premier League is now more than double the amount spent in the next highest-paying league -- Serie A -- for the first time ever. The Premier League's 20 clubs spend around £2.3bn on wages per season.
Barcelona and Real Madrid, French champions Paris Saint-Germain and Bundesliga giants Bayern Munich make up the nine European "super clubs."
- Nick Harris (@sportingintel) 12 January 2017
The report said the clubs have become "global brands" and each has boosted their annual income by up to £100 million through commercial sources, principally sponsorship deals.
That increase is around £99m ahead of the average increase for the other top division clubs throughout Europe.
UEFA president Aleksander Ceferin warned in the report of the threat of "a return to high wage growth and the increasing concentration of sponsorship and commercial revenue among a handful of clubs."
The report added that the biggest clubs were "able to monetise their huge supporter bases, which extend across the globe and which can be accessed far better through social media than was ever possible through traditional marketing.
It also showed that UEFA's "financial fair play" rules had helped stem financial losses, with the trend of clubs spending much more than they earn having almost disappeared.
Ceferin said: "It shows that UEFA's regulatory role in financial fair play has not only steadied the ship of European finance but also provided the framework for unprecedented growth, investment and profitability."