The proposed Super League was announced on April 18th last year, although nine of the competitions' 12 founding clubs moved to renounce the idea within days after it provoked a fierce backlash from across the footballing world.
However, Madrid, Barca and Juve remain committed to the project, with Bianconeri president Andrea Agnelli reportedly keen to kick-start a new proposal.
Speaking at the Financial Times' Business of Football Summit in London, at which Agnelli was present, the UEFA president has now hit out at the clubs' owners for discussing the return of the controversial competition during the midst of Russia's invasion of Ukraine.
"First they launched [this] nonsense idea in middle of a pandemic," Ceferin said of the club owners. "Now we are hearing they are launching another in a war.
"They must live in a parallel world."
Ceferin has previously labelled Agnelli, as well as the Spanish giants' presidents Florentino Perez and Joan Laporta, as "incompetent", and accused them of trying to "kill football".
Meanwhile, Ceferin also spoke about the sporting sanctions being placed on Russia in the aftermath of the invasion on Ukraine.
FIFA and UEFA have moved to expel Russian teams from its competitions, including the upcoming Women's European Championships in England, for which Russia had qualified, while St Petersburg has been stripped of this season's Champions League final.
Perez's controversial remarks came from an audio recording in 2006 that was leaked on Tuesday and published in Spanish newspaper El Confidencial.
At that time Perez had just left his position as Madrid president and in the audio he appears to at least partially link the influence held by the two players to his exit.
He is reported to have opined Casillas was not good enough to play in goal for Madrid while questioning the huge influence held by Raul.
Perez, who returned as Madrid's president in 2009, reckoned his support of the European Super League was the motivation behind the leaked audio.
In a statement released by Real Madrid, Perez said: "Given the story in El Confidencial, in which comments are attributed to me, I think it's necessary to clarify.
"The comments were made in conversation with D. Jose Antonio [Abellan], who has been unsuccessfully trying to sell them for years. It's surprising that given the time that has passed, they have appeared today in the newspaper El Confidencial.
"The comments are taken out of the context in which they were made. That they are reproduced now, after so many years, I believe is due to my role as one of the promoters of the European Super League.
"I have placed the issue in the hands of my lawyers who are studying possible legal action."
Former striker Raul is Madrid's all-time record appearance holder with 741 and was their leading goalscorer with 323 until that total was eclipsed by Cristiano Ronaldo, who found the net 450 times for Los Blancos.
Raul is currently coach of Madrid's reserve team.
Ex-goalkeeper Casillas is just behind Raul with 725 appearances and won all the major club titles during a 25-year stint with Madrid.
The Super League's launch last year failed spectacularly, with nine of the 12 founder clubs promptly withdrawing due to fan, media and player pressure.
However, Real Madrid, Barcelona and Juventus have stood by the plans.
Eighteen months on, A22 Sports Management – a company representing the Super League clubs – are now planning to revive the proposals.
Bernd Reichart, a media executive, has been appointed to head up the plans.
He told the Financial Times: "We want to reach out to stakeholders in the European football community and broaden this vision.
"Even fans will have a lot of sympathy for the idea. It is a blank slate. Format will never be an obstacle."
Reichart promised there will be changes made to the initial proposal, which was for 12 teams to be permanent members of the Super League, with other clubs invited on merit.
"There is a reassessment - there is a clearly stated move towards an open format and that permanent membership is off the table," Reichart said, echoing the sentiment of Barcelona president Joan Laporta, who called for the Super League not to be a closed shop.
"We want to see whether or not there is broader consensus about the problems facing European football."
Reichart is targeting a launch in the 2024-25 season, as he added: "If fundamental change is to come, we want to be prepared."
That is the view of finance expert Dan Plumley, who says the threat of Europe's elite clubs forming a breakaway competition is unlikely to ever go away.
Everton dropped into the Premier League's relegation zone after being deducted 10 points for a breach of the league's profit and sustainability rules earlier this month, with an independent commission ruling the Toffees exceeded the competition's maximum loss limit by £19.5million across four seasons between 2018 and 2022.
That penalty – the largest in the competition's history – has been fiercely protested by fans and has led to questions regarding other clubs' financial practices.
The Premier League is investigating City over 115 alleged breaches of the competition's rules, while Chelsea's finances are also being examined following allegations of secret payments made by companies belonging to former owner Roman Abramovich.
Some have suggested those clubs could face huge points deductions or even expulsion if found guilty, but Plumley believes that could push them back into the arms of the Super League.
"I don't think the European Super League will ever go away. I think we've seen that time and time again," Plumley told Stats Perform.
"It was the closest it's ever been to fruition in 2021, we know the backlash there but it's never off the table. You've seen the wider narrative in the European football landscape, and my take was that it would always come back around.
"It will be particularly dependent on what the Champions League looks like and the Champions League broadcasting revenues and reformat of that competition. So broadly speaking, I don't think it's off the table."
Both City and Chelsea were involved in the widely despised Super League project, which collapsed under pressure from fans, media and players in 2021.
Plumley is certain the Premier League will be in self-preservation mode when it comes to ruling on cases involving those clubs, saying: "I think the Premier League will be mindful of that.
"They know there is a lot of power held by those big clubs and their ownership structures and the people that are in that mix. They know that the threat of a Super League is still there.
"I do think that will be a factor in this, whether we like it or not. It will be there in the background of the considerations.
"There is that argument, in the same way as in the Champions League, that if the bigger clubs don't get what they want, or feel that they're being too heavily penalised, you can probably bet that a conversation about a European Super League will come back around.
"I think it would probably have come around anyway, but this kind of stuff might accelerate that. It might make it move quicker, but I don't think it was ever off the table."
Nine of the original 12 founding teams involved in the controversial project – including all six English clubs – have renounced the competition and promised to take all possible steps to remove themselves from it.
They all agreed a peace accord with UEFA last week that saw them recommit to the current structures of club and international football.
As part of the deal, those nine teams also accepted light punishments including goodwill payments to UEFA and a small portion of their prize money being withheld.
But Barca, Juve and Madrid are yet to terminate their involvement and on Saturday insisted the breakaway project was lawful, hitting out at "intolerable" pressure and vowing to persevere.
When announcing their agreement with the nine clubs who came back into the fold, UEFA said it would "take whatever action it deems appropriate" against the remaining three.
That process has now begun, as UEFA released a statement on Wednesday confirming the disciplinary probe.
It read: "In accordance with Article 31(4) of the UEFA disciplinary regulations, UEFA ethics and disciplinary inspectors have today been appointed to conduct a disciplinary investigation regarding a potential violation of UEFA's legal framework by Real Madrid, Barcelona and Juventus in connection with the so-called 'Super League' project.
"Further information regarding this matter will be made available in due course."
Speaking last week, UEFA president Aleksander Ceferin discussed the recent developments, praising the nine clubs for stepping back from the Super League.
"I said at the UEFA Congress that it takes a strong organisation to admit making a mistake especially in these days of trial by social media," he said.
"In accepting their commitments and willingness to repair the disruption they caused, UEFA wants to put this chapter behind it and move forward in a positive spirit.
"The measures announced are significant, but none of the financial penalties will be retained by UEFA. They will all be reinvested into youth and grassroots football in local communities across Europe, including the UK.
"These clubs have done just that, recognised their mistakes quickly and have taken action to demonstrate their contrition and future commitment to European football.
"The same cannot be said for the clubs that remain involved in the so-called 'Super League' and UEFA will deal with those clubs subsequently."
