European clubs are looking at new options for the future of the Champions League after a proposal that would have given captive places to 24 teams ran into strong opposition, sources with knowledge of the matter said on Monday.

The chairman of the European Club Association (ECA) Andrea Agnelli also appeared indicate that the contentious plan had hit the rocks, acknowledging in a speech on Monday that its members had different views on the matter.

- Champions League group stage: All you need to know

UEFA has been working with ECA, which represents 232 clubs, on reform of the European club competition system from 2024 onwards.

The initial proposal envisaged a three-tier pan European league with promotion and relegation between the divisions.

The top tier would be the new version of the Champions League but 24 of the 32 teams would keep their places for the following season, breaking the tradition that qualification is achieved through performance in domestic competition.

It also suggested four groups of eight in the group stage, meaning a large increase in the number of European matches.

However, the proposal was strongly opposed by Europe's domestic leagues that say the battle for Champions League places is a key aspect of their competitions. A number of ECA members then broke ranks after a meeting in Malta in June and also criticised the plan.

Sources close the to clubs said on Monday that other proposals were now on the table.

These included one which suggested groups of six for the Champions League and another proposed by FC Copenhagen which would change the criteria which decides the allocation of places.

At present, slots are allocated to clubs depending on where they finish in their respective domestic leagues, with the top four teams from England, Spain, Italy and Germany earning direct qualification for the Champions League group stage.

However, FC Copenhagen proposed that historical records of the clubs should also be taken into account -- which would favour big clubs from middle-ranking leagues over smaller clubs from top-ranked leagues.

"The feeling before Malta was that everything was written in stone. You've all seen it's not like this," Agnelli told the ECA general assembly, without directly mentioning the proposal.

"It's been great seeing the participation of many clubs in sharing consultation in the past couple of months. This was the start of a genuine, open and transparent process."

"We have different views on formats and the stability principles. We have issues on the calendar. I understand that -- but there is an overall acceptance that reform must happen in 2024-25."

He also struck a conciliatory note towards the needs of the leagues. "We strongly believe that whatever the future holds ... we must maintain a strong symbiosis with domestic leagues."