Mark Clattenburg believed he had Howard Webb’s approval to approach Paul Tierney

Mark Clattenburg approached referee Paul Tierney for a meeting on behalf of Nottingham Forest on Saturday because he believed that PGMOL chief Howard Webb had granted him permission to act as a conduit between the club and officials, Telegraph Sport understands.

The fallout from events at the City Ground on Saturday continues with fresh claims that Clattenburg, once one of Europe’s highest profile referees, now working for Forest, reached the arrangement at a meeting between Webb and Forest officials on February 28.

PGMOL, the organisation that runs referees and assistants in England, led by Webb, has indicated that it believes no such agreement was in place for Clattenburg to speak to referees post-match. There is no dispute that the meeting took place at Forest’s training ground ahead of the FA Cup tie against Manchester United that same evening which Webb, PGMOL chief refereeing officer, attended.

Clattenburg was told at the meeting that he could not go into the referees’ room before games on behalf of Forest. He had done so ahead of the home win against West Ham on February 17. It is understood that Webb asked him not to do so again. But Clattenburg believed that he left that meeting with an agreement that he could approach the referee for a conversation 30 minutes after the end of a game, as managers, staff and players are permitted to do so.

Those conversations are at the referee’s discretion. PGMOL (Professional Game Match Officials) has indicated that it believes no confirmation was given either way to any agreement. Clattenburg went to see Tierney after Saturday’s game and the erroneous drop ball incident in time added on. He entered the room briefly with Nuno’s assistant Rui Pedro Silva. Tierney then asked Clattenburg  to leave.

PGMOL is understood to believe that Clattenburg never entered the room. PGMOL say the training ground meeting on Feb 28 was standard procedure to speak to a newly-appointed Premier League manager. Although Nuno had worked in the Premier League before, there is a new behaviour guide for managers and coaches as well as law changes and new interpretations. Nuno, Clattenburg, Webb and Jon Moss, manager of PGMOL’s top tier referees, were among those who attended. Webb was later at the City Ground for the FA Cup tie where the club sat him next to Clattenburg.

The protocol is that only players and staff named on the official list submitted to the Premier League game by game can approach the referee after a game. Clattenburg’s case to Webb and PGMOL has been that he could be a useful intermediary in explaining the law and its interpretation to Forest staff and directors.

In the aftermath of Darwin Nunez’s 99th minute goal, and the final whistle, the Forest coach Steven Reid was sent off by Tierney for abusive language. Evangelos Marinakis, the Forest owner who appointed Clattenburg, was in the tunnel area. Clattenburg confirmed in an interview with the Telegraph conducted after the game that he had not been permitted to speak to Tierney.

Tierney had erred in not awarding a drop ball to Forest after stopping the game for a head injury to Ibrahima Konate while the ball was in the home team’s possession. Liverpool scored almost two minutes later and with the ball having gone out of play in the interim. Forest have not submitted a complaint to PGMOL since Saturday and are unlikely to do so now that the dust has settled.

Clattenburg’s role, and his presence in the City Ground tunnel on Saturday, had caused bemusement among Premier League officials, especially given he was often himself heavily criticised by certain managers during his own career as a referee. Clattenburg was appointed by Marinakis last month as an advisor to the Forest board on a range of football matters.

One of his roles is to filter complaints on points of law and suggest when Forest have a strong case, and when they do not. He will also advise the coaching staff on how the players can manage games and stay on top of law changes. It is the first time a former referee has been appointed to a club in such a high-profile role and it is possible that others may follow suit. PGMOL will admit that Tierney did make an error according to the law of the game on the drop ball on Saturday.

Reid has been charged by the Football Association with “abusive and/or insulting language to a match official” before and after his sending off. He has also been charged with acting in an “improper manner” after his dismissal. Forest have been charged with failing to ensure players and coaches did not “behave in an improper way” after the end of the game.

As well as his role at Forest, Clattenburg has taken the role of referee on the relaunch of the famous ITV show Gladiators. He will be a pundit for the US network Fox Sports for the European Championship finals this summer. He is also a columnist with the Daily Mail.