What is the European Super League and how would it work?

On 18 April, 12 of Europe's top soccer clubs announced they were launching a breakaway Super League. Just three days later, the six UK clubs involved have pulled out, and the project is on hold.

In a statement, the Super League said: "Given the current circumstances, we shall reconsider the most appropriate steps to reshape the project, always having in mind our goals of offering fans the best experience possible while enhancing solidarity payments for the entire football community."

It follows objections from key soccer governing bodies, including UEFA which runs the Champions League, and the UK Prime Minister Boris Johnston.

UEFA president Aleksander Ceferin said it was "admirable" for the UK clubs to admit they had made a mistake.

“The important thing now is that we move on, rebuild the unity that the game enjoyed before this and move forward together," he said.

Here are five key questions answered about the European Super League project.

The European Super League is effectively an alternative to the Union for European Football Associations (UEFA) Champions League, which would guarantee places in the competition to the founding clubs, rather than requiring qualification through their domestic leagues.

It was due to be financed by US investment bank JP Morgan, with a $4.2 billion grant for the teams to spend on infrastructure and recovery from the impact of the COVID-19 pandemic.

Six from the English Premier League: Manchester United, Manchester City, Liverpool, Arsenal, Chelsea and Tottenham Hotspur, which have now pulled out. Three more hail from Spain: Real Madrid, Barcelona and Atletico Madrid. And the final three come from Italy: Inter Milan, Juventus and AC Milan.

In a statement, the Super League said it had planned to launch "as soon as practicable" and add three more teams as founder members to bring the total to 15.

A 20-team midweek league would run, with five teams qualifying each season "based on their achievements in the prior seasons".

The format of the competition would be two groups of 10 playing home- and away fixtures with the top three in each group qualifying for the quarter-finals. A play-off involving fourth and fifth placed teams would complete the final eight.

There were also plans to launch a women's Super League competition after the men's league is up and running, Reuters reports.

Announcing the league, its Vice-Chairman and Juventus President Andrea Agnelli said the move would secure the long-term future of the game, following the economic fallout of the COVID-19 pandemic.

Most clubs have been hit hard by the lack of spectators over the past year, and many have sizeable debts, reports the BBC.

The Founding Chairman of the Super League, Real Madrid President Florentino Perez, said: "We will help football at every level and take it to its rightful place in the world. Football is the only global sport in the world with more than 4 billion fans, and our responsibility as big clubs is to respond to their desires."

UEFA held an emergency meeting about the Super League on Monday and said players and clubs could be banned from UEFA competitions - including three of this season’s Champions League semi-finalists.

British Prime Minister Boris Johnson objected to the plans and the UK government is looking at options to penalize the six English teams that have signed up.

In January, the world's soccer governing body, FIFA, warned that any breakaway league would not be recognized by them, warning players involved could be banned from taking part in the World Cup.

The Super League letter urged FIFA and UEFA to agree to talks, Reuters reports, and said they wanted the breakaway league to exist alongside current European club competitions.

Guaranteed spots go against long-standing tradition in European soccer, but the founding clubs argued it would create a more sustainable financial model.

"The formation of the Super League comes at a time when the global pandemic has accelerated the instability in the existing European football economic model," they said.

But even fans of the clubs involved have condemned the move, while British broadcaster BT Sport - which airs the Champions League - said the Super League could have a "damaging effect [on] the long-term health of football in this country".