Mike Hewitt/Getty Images

Arsenal, Chelsea and Manchester United are no longer being investigated under UEFA's financial fair play guidelines. The European governing body has announced fewer than 20 clubs face further inspection—down from February's total of 76—as reported by Bryan Swanson of Sky Sports:

European football's governing body will not disclose the identity of the clubs involved and whether any are English. Arsenal, Chelsea and Manchester United have told Sky Sports News they are not under investigation. UEFA's independent club financial control body (CFCB) will meet on Tuesday for two days in Nyon, Switzerland and discuss further action for clubs that fail to meet its financial requirements.

Michael Steele/Getty Images

While UEFA are yet to decide upon a punishment for those found to be in breach of the new rules, reprimands are likely to be severe. Swanson's report suggests warnings, fines and bans from competitions may be used, as well as the potential removal of a title or accolade.

UEFA says "clubs can spend up to €5 million more than they earn per assessment period (three years)," although this can be exceeded if the additional funds are "covered by a direct contribution/payment from the club owner(s) or a related party."

The limits stand at €45 million for this season and €30 million for the next three years at the conclusion of the current campaign. The number will continue to decrease across the following years, although exact sums are yet to be determined.

A "spend what you earn" strategy looks to be effective here, as big clubs can no longer afford to luxuriously purchase world-class stars for the sake of filling their squads.

We've seen this with Chelsea across the past few months, who were forced to sell Kevin De Bruyne and Juan Mata in order to secure Nemanja Matic, Mohamed Salah and Kurt Zouma without fear of punishment, noted by Tony Banks of the Express:

Mourinho has been told there will be no money on top of what he brings in from sales, as Chelsea try to stay within Financial Fair Play rules. And that could even mean a departure for long-serving goalkeeper Petr Cech, who is still only 31 and coveted by many top clubs. Chelsea have brilliant young Belgian keeper Thibaut Courtois on loan at Atletico Madrid.

Harold Cunningham/Getty Images

UEFA confirms the financial fair play stipulation has been added "to promote investment in stadiums, training facilities and youth development," thus eliminating many unnecessary transfer fees from European football.

Manchester City and Paris-Saint Germain officials will be the most nervous until they are given the green light. Although not confirmed to still be under investigation, neither club has revealed otherwise, despite being part of the original 76, reported by Martyn Ziegler of the Press Association and via the Daily Mail.

They are two examples of mega-rich clubs who continue to strengthen their squads. City have posted total expenditure of £91,777,840 this season, £15,532,000 last year and £57,318,800 in 2011, according to TransferMarkt.com, signaling the Etihad club could soon face trouble.

In comparison, PSG's spending also maxes out at £96,272,000 this season, £129,533,684 in 2012 and £85,096,000 the year before, per the same website.

Both sides have enjoyed domestic titles during this time, but are yet to prove themselves on the European stage. City were eliminated at the Champions League round of 16 stage by Barcelona this season, while PSG recently suffered a late quarter-final defeat to Chelsea.

It must be stressed neither side is confirmed to still be under the spotlight, but these are the types of numbers which could land clubs in trouble.

UEFA's first set of punishments will set a precedent here. Withdrawing a title win is undoubtedly the most extreme measure threatened, while a fine would have to be substantial to significantly impact those who fail to comply.

Perhaps a transfer ban—much like that imposed on Barca by FIFA for breach of its rules involving minor players—may suffice, per BBC Sport. This way clubs cannot spend with reckless intent and will be forced to sell until they break even.

Those still under investigation should be anxious. It's likely the governing body wish to make an example of those who fail to meet adhere to their standards, providing UEFA with an opportune moment to show the guidelines should be taken seriously.

Follow @Nakerman