The four - West Ham's rivals in the quest to avoid relegation from the Premiership - met in central London on Friday to discuss the punishment, which many had expected to include a points deduction.

And a statement released on Friday night by the four clubs and sent to the Premier League's board of directors confirmed: "You should understand we are separately in the process of obtaining legal advice arising out of the terms of the decision.

"You can expect to hear from us in relation to this in the early part of next week.

"In the meantime, all our rights in that respect are reserved."

The statement from the clubs said: "The board are given power under the rules to 'inquire into any suspected or alleged breach of these rules...

"The FAPL have a duty to act in good faith and with reasonable diligence.

"That duty extends to investigating an alleged breach of the rules where there is some apparently credible evidence of a breach.

"Furthermore, given the potential significance to our clubs of any further serious breach of FAPL rules by West Ham at this point in time, not to investigate immediately would be a breach by the League of their obligation of utmost good faith to us under FAPL rule B13.

"In the light of the above it is incumbent upon the board forthwith to investigate this matter."

The statement continued: "We require your urgent confirmation that that FAPL will act as set out above in this letter.

"If we do not receive that confirmation, we will take all such steps as are available to us to enforce and protect our rights, including taking urgent advice with a view to convening a meeting of the FAPL and/or bringing proceedings in court under Section 459 of the Companies Act 1985, on the basis that the affairs of the Company are being conducted in a manner which is unfairly prejudicial to us."

The Premier League have also taken legal advice however, and have been told their position is unassailable.

The League's position is that it is entirely up to the independent commission to decide on the punishment, and that if they had any influence over the decision it would be a conflict of interest.

They would argue the commission had a full range of sanctions available to it, and that Premier League rules do not state what the punishment should be for such rule breaches.

A Premier League spokesman on Friday night said: "We will study the contents of the letter and respond accordingly."

West Ham are also unconcerned by the prospect of possible legal action.

Hammers' chairman Eggert Magnusson has a great deal of experience of cases regarding player eligibility from his time in UEFA and FIFA, and never viewed the club's breaches - which took place before he took over - as likely to result in a points deduction.

Wigan chairman Dave Whelan believes the independent commission should have hit West Ham with a 10-point penalty after they found the club guilty on two charges of transfer irregularities, rather than fining them £5.5million.

The clubs will claim points penalties have been issued before for offences they would argue were less serious.

Middlesbrough were deducted three points a decade ago for failing to fulfil a fixture as 16 players were either ill or injured, a judgement which condemned them to relegation from the Premiership.