UEFA is set to outline proposals to change the format of the Champions League from 2024 in a meeting of its 55 national association members on Tuesday.
The governing body is hoping the new format, which will guarantee clubs more games and revenue, will avert the threat of a breakaway European Super League.
The new format would increase the number of clubs taking part in the competition from 32 to 36 with each team guaranteed at least 10 games against different opponents and the current group stages replaced by a single league based on the so-called "Swiss model".
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Although the European Leagues - the body that represents domestic leagues across Europe - believes this system is "an improvement compared to more radical proposals that emerged in 2019", there is still "strong concerns" over the impact of more matchdays on domestic competitions.
Their mission is to maintain the competitive balance between and within domestic competitions with the accommodation of an additional four games in the autumn likely to be a challenge for many leagues, including England where the Carabao Cup's future could be under severe threat.
The members of the European Leagues - made up of 37 competitions from 30 different countries including England's Premier League - have already met to discuss the proposals.
Under the new proposals, it is understood three clubs will qualify based on their UEFA co-efficient which looks at past performance, meaning European heavyweights such as Manchester United and Real Madrid could still qualify even if they missed out on qualification via the conventional route.
It is believed qualification for the last 16 would be changed so that the top eight teams in the 36-team league would automatically reach the knockout phase, while the next 16 teams in the table would play off for the final eight places.
Altogether there would be 225 matches in the competition compared to 125 now.
Sky Sports News also understands various views were expressed when the proposals were put to shareholders during a Premier League meeting last week.
'Safety net would create closed league'
Offering clubs a qualifying place based on past performance in a new-look Champions League format would create a "de facto closed league", according to European Leagues president Lars-Christer Olsson.
Olsson, a former UEFA chief executive, told The Times: "For me, it's a principle that the historic coefficient should not be part of an international competition at all. We will have a de facto closed Champions League."
UEFA's proposals could mean as many as six teams qualifying from a single league, such as the Premier League, in future.
In addition to the three extra co-efficient places, France is understood to be being offered a fourth automatic position in an expanded 36-team group phase.