What's next for Kylian Mbappe? It's the question on everyone's lips after his Paris Saint-Germain teammate Neymar committed his future to the French club until 2025. With all the talk around Borussia Dortmund star Erling Haaland and his future, the 22-year-old Mbappe is arguably an even bigger talent and every top club in Europe is keen to sign him if he doesn't renew his contract, which expires in 2022.

The 2018 world champion -- signed by PSG for a whopping €180 million from Monaco the same summer -- is the one young player who's shown the class, quality and consistency to suggest he will take over the mantle of 'best in the world' from Cristiano Ronaldo and Lionel Messi.

But, despite PSG working overtime for months on a new contract -- with Mbappe and sporting director, Leonardo, repeatedly declaring his optimism that it will happen -- it's yet to materialise. The youngster is rumoured to want parity with the club's runaway top earner, Neymar, who has just penned terms of €30m-a-year, which could be a sticking point for potential suitors.

So what are the possibilities for Mbappe? ESPN has assessed the moves open to him.

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REAL MADRID

With sources telling ESPN that Messi will be handed a three-year contract to persuade him to stay at Barcelona, and taking into account the Catalan club's €1.2 billion debt, if Mbappe ended up in Spain it would likely be at rivals Real Madrid.

In the wake of the terribly managed Super League debacle, it would seem somewhat out of tune for the Madrid giants to offer one of the most lucrative contracts in the history of the club (let's not forget: their main justification for backing the breakaway league was a lack of ability to operate according to sound economic principles within the current La Liga and Champions League context). Yet that's unlikely to bother them, especially as one could argue that Mbappe is one of the few players that could become the money spinner Real Madrid need when the refurbished Santiago Bernabeu -- complete with tours and museum -- opens to the public.

With 33-year-old Karim Benzema the only credible central striker/forward option for Madrid currently, there's no question that manager Zinedine Zidane could do with Mbappe on the pitch (and the player himself seems keen to play for Zizou as well.) The PSG forward could also benefit from Benzema's mentorship and duo look a compatible partnership -- though they've never had the opportunity to prove it for Les Bleus as Benzema hasn't featured for France since 2015.

However, while Real Madrid would surely have found a way to offer Mbappe an attractive salary if he'd been at the end of his contract this summer, it's less likely that they'd be able to find the €100m-€125m fee that it would conservatively take to persuade PSG to let him go. Indeed, it would take a massive clearout of the likes of Gareth Bale and Eden Hazard, which in the current financial climate could be something of a struggle.

A move to Madrid seems a lot more likely in the event that Mbappe simply plays out his remaining deal with PSG and joins on a free in 2022.

LIVERPOOL

Having previously been complimentary of Jurgen Klopp's brand of football at Liverpool, as well as the club as whole, it's legitimate to assume that a move to Anfield would have been close to the top of Mbappe's list if he could choose freely.

But with Liverpool's Champions League hopes withering away this season - and the recent transfer policy of owners FSG offering few promises of an imminent spending spree -- only the incredibly optimistic fan would still be entertaining the prospect of Mbappe making a grand entry in the summer.

Though the oft-mooted idea of Liverpool forward Mohamed Salah moving in the opposite direction as a part of a deal is a possibility which appeals to all parties, it still doesn't quite add up -- given the climate of anger created by the Super League and ongoing COVID-19 pandemic -- that Liverpool would smash their transfer record and wage structure on a "superstar" signing, even if they were to snatch a Champions League spot.

MANCHESTER UNITED

As opposed to the noises coming out of the majority of the other Super League renegades, there's little to suggest that austerity is on the agenda at Old Trafford this summer. On the contrary, the Glazer family might be intent on landing one or two top-class names, partly to appease disgruntled fans and partly to build on the momentum of a relatively successful season to make a proper assault on the Premier League title.

Manchester United are among the few clubs who could satisfy both PSG and Mbappe financially, even being able to justify (and monetise) such an investment from a commercial point of view. The presence of his France teammate Paul Pogba -- who appears more settled than he's ever been at Old Trafford -- is certainly not a disadvantage. And despite the performance levels of Manchester United's attacking players progressing over the course of the season, there's still room for arguably the top forward in world football to join forces with his old teammate Edinson Cavani, as well as young stars Mason Greenwood and Marcus Rashford.

But while Manchester United could be a dark horse in the race for Mbappe, it'll still take an awful lot of bargaining to strike a deal with PSG.

STAY AT PARIS SAINT-GERMAIN

Despite all the interest, and even with Mbappe's contract having just a year left to run, PSG won't want to let their star depart. Considering his exceptional qualities, they'd still be loath to accept double his "market value" of around €200m, even if it were offered, which makes this case a completely different proposition to other instances of players on expiring deals.

Hence, given the exceptional complexities, it's probable that Mbappe will remain at PSG -- either by signing a new long-term deal, in the summer or later in the year (which may include an agreement to let him leave, with the club's blessing, in two or three years), or simply seeing out his contract this season but departing on a free transfer in 2022.

The latter scenario would obviously provide Mbappe with a plethora of options; his father Wilfried can negotiate freely without having to worry about PSG, which could also put Manchester City in the frame -- though Tottenham's Harry Kane and Dortmund's Haaland have been linked more, while the two clubs' political backgrounds (they are owned by rival Gulf states, UAE and Qatar) make a deal for Mbappe virtually impossible.

PSG will consider that they have a year to convince Mbappe to stay and win the coveted Champions League trophy after two years of close calls. If they still haven't made any progress by January then they may start to think about other options.

VERDICT

Should Mbappe leave this summer, the most likely scenario is for the player himself to force a move. But don't forget that he's Parisian born and bred, and is reportedly much happier at the club now under new coach Mauricio Pochettino than he was with Thomas Tuchel.

A suitor would have to convince Mbappe about their amazing sporting project and offer him a big pay packet and transfer fee to match, and it's possible that Real Madrid may be his only option in this regard. Even then, in these uncertain times, it's unlikely that Mbappe will move this summer. Which just makes 2022 all the more important.

Information from ESPN's Julien Laurens was used in this report.