The FA is investigating an allegation that referee David Coote discussed giving a yellow card before a match.
The Sun newspaper claims Coote booked then-Leeds player Ezgjan Alioski in a match against West Brom in October 2019, then messaged a friend saying: "I hope you backed as discussed."
The Sun is reporting that Coote denies any wrongdoing.
A spokesperson for PGMOL told Sky Sports News: "The facts need to be established in light of these very serious allegations.
"We adopt a zero-tolerance approach to any breach of our integrity code of conduct, which is signed by all match officials on an annual basis. PGMOL board is committed to taking the appropriate action should any breach of that code be proven.
"David Coote remains suspended and subject to an ongoing disciplinary process by PGMOL, separate to the investigation into this matter, which will be carried out independently by the FA.
"We will be making no further comment at this stage."
A spokesperson for the FA told Sky Sports News: "These are very serious allegations and we are investigating as a matter of urgency."
Leeds are aware of the latest allegations but do not wish to comment at this time.
(c) Sky Sports 2024: David Coote: FA investigating allegations referee discussed giving yellow card before Leeds-West Brom match
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