Manchester City manager Pep Guardiola spoke out against the proposals for a ‘closed-shop’ European Super League that his own club have signed up to as opposition to the plans ramped up on Tuesday.

While insisting he wanted to learn more about the details of the plans and admitting he felt uncomfortable answering questions on it, Guardiola was clear on his views of any competition in which there is no promotion of relegation.

“It is not a sport where the relation between effort and success does not exist,” Guardiola said.

“It is not a sport where success is already guaranteed. It is not a sport where it doesn’t matter when you lose.”

And Guardiola called on those behind the plans – including his own bosses – to offer more information.

“They have the obligation, the duty as soon as possible, today better than tomorrow, to come out all around the world and clarify the situation that is to come, and the benefits and why they took the decision,” he said.

City have joined Liverpool, Manchester United, Tottenham, Chelsea and Arsenal – the so-called ‘Big Six’ of English football – as well as AC Milan, Atletico Madrid, Barcelona, Inter Milan, Juventus and Real Madrid in signing up for a breakaway competition which has drawn widespread opposition.

Guardiola has now joined Liverpool counterpart Jurgen Klopp in questioning the vision of their own clubs in supporting the plans which emerged in a bombshell announcement on Sunday.

But Ryan Mason, newly installed as Spurs manager until the end of the season – after Jose Mourinho’s sacking on Monday – said he had not had time to read the details of the project given events at the club.

“It would be wrong of me to answer a question that I don’t know anything about,” he said.

Real Madrid boss Zinedine Zidane refused to be drawn on the matter during his own press conference on Tuesday, following the example of Chelsea’s Thomas Tuchel 24 hours earlier.

But – as Manchester United supporters’ groups consider removing banners from Old Trafford to register their opposition – Red Devils forward Marcus Rashford notably shared an image carrying a quote from the club’s great former manager Sir Matt Busby which reads: “Football is nothing without fans.”

Rashford’s team-mate Luke Shaw later expressed took to Twitter to express his concern that the new “changes could impact the sport that I and millions of others love”.

He wrote: “Not a minute has passed when I haven’t thought about the current situation.

“I wondered how I could express my opinion without causing any issues for my club, which everyone knows I care about deeply.

“There is so much passion around the world for football and I have been privileged to experience that first-hand, however I worry that these changes could impact the sport that I and millions of others love.

“We’ve been without supporters in stadiums for over a year now and I know how much myself and the team have missed them in each and every game. Fans and players should always have a voice and their opinion should always be counted.”

The proposals have prompted a backlash from governing bodies, fans and politicians on all sides.

The remaining 14 Premier League clubs met on Tuesday to discuss the next steps, while several issued their own individual statements of opposition.

Everton strongly criticised the “preposterous arrogance” of the clubs involved, accusing them of “betraying” football supporters around the country.

“The self-proclaimed Super Six appear intent on disenfranchising supporters across the game – including their own – by putting the very structure that underpins the game we love under threat,” a statement said.

“The backlash is understandable and deserved – and has to be listened to.

“This preposterous arrogance is not wanted anywhere in football outside of the clubs that have drafted this plan.

“On behalf of everyone associated with Everton, we respectfully ask that the proposals are immediately withdrawn and that the private meetings and subversive practises that have brought our beautiful game to possibly its lowest ever position in terms of trust end now.”

West Ham said they were “vehemently opposed” to the plans.

“These proposals are an attack on sporting integrity, undermine competition, and ignore those supporters, and those of the thousands of clubs and millions of players, from the Premier League to Sunday League, who can aspire to reach the top of the game just like our 150-plus homegrown Academy of Football graduates who came from grassroots and were developed into first-team players,” a statement said.

Former Chelsea captain and current Aston Villa coach John Terry posted an update on Instagram looking into the distance with the caption: “What has happened to our beautiful game…”

Brendan Rodgers, whose Leicester side are on course to qualify for the Champions League next season, said in his own press conference that the plans were a demonstration of business overtaking sport.

“There has been a line drawn in the sand with all of this,” he said. “It has moved across from what looks very much like a purely business proposal.

“All the merits of teams and rewards in sport, it looks like from the outside that isn’t really taken into the ideas going forward.”

Brighton said the proposals showed a “clear lack of respect” for the other clubs across Europe.

“Brighton and Hove Albion are totally opposed to plans for a breakaway European Super League as it would destroy the dreams of clubs at every level of the domestic game,” a statement said.

“These plans are the latest in an alarming and growing list of clandestine attempts from a small group of clubs whose actions would be wiping out close to 150 years of football’s tradition, competition, and sporting progress through merit.”

Meanwhile, Burnley chairman Alan Pace called on the Government to act by introducing an independent regulator to protect football.

In an open letter, he wrote: “As a former financier, I understand the commercial considerations for these clubs and can appreciate their frustration at being the largest revenue drivers for the UEFA Champions League, without receiving the same levels of influence and reward.

“However, this is a move which does not treat fans or the game’s history with the respect it deserves and is not the solution.”

But former England boss Sven-Goran Eriksson has predicted that the Super League will never get off the ground in its current format and urged its architects not to kill the “dream” of football.

The Swede told ITV’s Good Morning Britain: “I don’t know what’s going to happen, but I can see that something will happen and something will be changed.

“But that six, 12 teams in Europe, or 20 teams you’re taking about, would create their own league? I can’t see that, I can absolutely not see it and I strongly say, ‘No, don’t do it’ because that will take away the dream of football.”

The Premier League’s record goalscorer Alan Shearer expressed his “shock and disbelief and disgust” at the move, and suggested the tide of fury which has greeted it might prompt some of those involved to think again.

Shearer told BBC Breakfast: “I would think that there are directors and people who help run their football clubs, they probably didn’t even have a clue that this was coming out.

“This has probably just just come out from greedy owners who want their cake and to eat it.

“But when you look at the reaction over the last 36 hours, common sense would tell you that these clubs will have to go away and think, ‘Have we really done the right thing here?’”

Notably, both Paris St Germain and Bayern Munich have not joined the project and have spoken in opposition.

PSG president Nasser Al-Khelaifi said: “Paris Saint-Germain holds the firm belief that football is a game for everyone.

“I have been consistent on this since the very beginning. As a football club, we are a family and a community whose fabric is our fans – I believe we shouldn’t forget this…

“We believe that any proposal without the support of UEFA – an organisation that has been working to progress the interests of European football for nearly 70 years – does not resolve the issues currently facing the football community, but is instead driven by self-interest.”

Bayern president Herbert Hainer said: “Our members and fans reject a Super League.

“As FC Bayern, it is our wish and our aim that European clubs live the wonderful and emotional competition that is the Champions League, and develop it together with UEFA. FC Bayern says ‘no’ to the Super League.”