Nottingham Forest face the threat of Football Association and Premier League charges over their extraordinary attack on the officiating of their match against Everton on Sunday.

Three Forest members of staff – head coach Nuno Espirito Santo, referee analyst Mark Clattenburg and full-back Neco Williams – have been asked by the FA to explain comments they made about the refereeing at Goodison Park, while the Premier League is also examining the club’s social media post which appeared to question the integrity of VAR Stuart Attwell.

The statements from the authorities came within hours of Forest demanding the release of VAR audio related to the rejection of three penalty appeals during their 2-0 defeat.

Forest first issued a club statement on X on Sunday, minutes after the final whistle, in which they said they had “warned” referees’ chief Howard Webb that Attwell “is a Luton fan” but that no change was made to the match appointment.

The club went further on Monday evening and called on Professional Game Match Officials Limited (PGMOL) to change its rules on officials’ allegiances to account for “contextual rivalries in the league table”, not just local rivalries.

The Premier League said it was “extremely disappointed” by the statement issued on Sunday and added: “It is never appropriate to improperly question the integrity of match officials, and the nature of these comments means the Premier League will also be investigating the matter in relation to the league’s rules.”

Sources have since told PA that Clattenburg did contact Webb on Friday to share that he thought Nuno might be asked about Attwell by the media, but that Forest did not raise Attwell’s appointment as a concern or make a request to change the appointment.

Forest stood by their initial position and went further on Monday, stating: “This was an issue we raised with PGMOL prior to the fixture because of the fear of the side show that would ensue if anything went wrong with officiating in the game. That fear has materialised, as the correctness of three important decisions against the club have been called into doubt.

“This is not about individuals but rather how the integrity of the game is seen. We know match officials do not allow outside factors to influence their decision-making and that all referees are required to declare their ‘allegiances’ to PGMOL to avoid any perceived conflict or harm to the game’s reputation for integrity.

“However, it is clear PGMOL must amend its rule on allegiances to account for contextual rivalries in the league table, not just local rivalries. This is currently not within the criteria but should be. Mere reliance on match officials to recuse themselves if contextual rivalries exist invites conjecture, as some have recused themselves where others have not.

“NFFC stands by its request for greater transparency around PGMOL appointments to further protect the game’s reputation, as intended in PGMOL’s existing approach to allegiances.

“Given the widespread and ongoing concerns, not merely of the fans, players and managers of this club but of many others and the pundits too, over VAR decisions throughout this season any move which boosts confidence in the system should be properly considered.”

Forest felt aggrieved that challenges by Everton’s Ashley Young on Giovanni Reyna and Callum Hudson-Odoi were not given as spot-kicks, and also felt Young should have penalised for handball inside the box.

Clattenburg wrote a column in the Daily Mail in which he said the situation could have been avoided if PGMOL “made smarter appointments”.

“Referees do not make mistakes deliberately but this was mind-boggling to watch. Why Attwell did not send Taylor (referee, Anthony) to his screen, only he will know.”

Nuno was asked whether he thought it was appropriate for the club to complain about the appointment of officials before a match, and said: “I prefer not to answer if it is appropriate.

“It’s a feeling and trying to avoid what happened today and not raise any more suspicions or thoughts that no one wants. It is about preventing.”

Forest defender Williams told Sky Sports he thought any of the top six teams would be “getting every single one” of the penalties Forest felt they should have been awarded.