A third European club competition could be introduced alongside the Champions League and Europa League from 2021, according to the head of the association of Europe's biggest teams.
European Club Association (ECA) chairman Andrea Agnelli, who is also on Uefa's executive committee, said "the green light has been given".
He did not give any more details on how the tournament would be organised.
"The current model needs modernising," said Agnelli.
Agnelli, who is also chairman of Italian champions Juventus, said: "A detailed assessment of the existing international match calendar is required prior to presenting a new model post-2024."
Speaking at the annual general assembly of the ECA in Croatia, he said the third competition would increase the number of clubs involved in European football from 80 to 96.
The idea, which could be approved by Uefa at a December meeting in Dublin, would see the Europa League reduced from 48 teams to 32 so that the Champions League, Europa League and the new competition would all have the same number of competitors.
The Cup Winners' Cup - for domestic cup champions - was scrapped in 1999.
In a statement, Uefa said it was "constantly reviewing the format of its competitions and is looking at a variety of options".
The European Leagues, the organisation that represents 32 leagues across Europe including the Premier League, Scottish Premiership and EFL, said it would fight the plans.
Deputy general secretary Alberto Colombo said: "We are not happy about the process at all, because this is something that has been prepared and cooked up by Uefa and the ECA without proper engagement."