Mark Clattenburg has left his role as Nottingham Forest's refereeing consultant, the Premier League club announced on Friday.
The former Premier League referee was appointed to the position in February. Since then, the club have been involved in several officiating controversies and has been criticised for making several statements against decisions made by Video Assistant Referees (VARs).
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"Since February this year, I have been proud to have done so under a consultancy agreement between NFFC and Referee Consultant Ltd," Clattenburg said in a statement.
"I performed my services under the consultancy agreement in good faith, to the best of my abilities and in the hope of using my extensive experience as a match official to help NFFC understand how decisions in relation to key match incidents are made amid the workings of VAR.
"However, it is now clear that the existence and performance of these consultancy services has caused unintended friction between NFFC and other participants, to the extent that it has become more of a hinderance than help to NFFC. It has also led to the unmerited targeting of me, personally, by certain participants and pundits.
"Such reactions and outcome was not expected and is regrettable, as it is my sincere belief that there is a place for and value in such a role in the modern game."
Forest have reacted angrily to a series of penalty decisions which they felt were unfair, calling into the question the integrity of VAR Stuart Attwell, a supporter of Luton Town who are in a battle with Forest to avoid relegation.
"Three extremely poor decisions -- three penalties not given -- which we simply cannot accept," the club said in a statement following their 2-0 defeat to Everton on April 21.
"We warned the PGMOL that the VAR is a Luton fan before the game but they didn't change him. Our patience has been tested multiple times. NFFC will now consider its options."
The following day, Forest released another statement making a formal request to refereeing body, the PGMOL, to release the VAR audio for the incidents at Goodison Park.
"We firmly advocate for the broader football community and supporters to have access to the audio and transcript for full transparency, ensuring the integrity of our sport is upheld," Forest said.
The Football Association (FA) on Friday charged Forest with misconduct for their initial statement, as well as manager Nuno Espirito Santo and defender Neco Williams for comments they made after the game. The FA charge alleges that the club, manager and player implied bias and questioned the integrity of match officials, which constitutes improper conduct.
The FA also formally warned Clattenburg "as to his future conduct" as a result of a newspaper article he wrote on the officiating.
A Premier League panel's findings, which have been seen by ESPN, unanimously said that a penalty claim for a foul by Ashley Young on Giovanni Reyna and a later handball by Young were unfounded and should not have led to a VAR intervention.
The panel did unanimously vote that Young should have been penalised for a spot kick in the second half for bringing down Callum Hudson-Odoi inside the area.
Forest are 17th in the standings with 26 points, having been docked four points for breaching the Premier League's profit and sustainability rules.