Celtic chairman Peter Lawwell has revealed he is stepping down from the club's board due to "abuse and threats".
The 66-year-old joined Celtic in 2003 as chief executive and held that position for 18 years, before returning in 2023 as non-executive chairman.
However, he and other members of the club's board have faced protests from supporters in recent months who have criticised their transfer activity and the long-term football strategy.
During a turbulent spell off the pitch, there was also public questioning of the transfer process by former boss Brendan Rodgers, .
An open letter, backed by hundreds of signatories, representing tens of thousands of fans, was also issued to the board, plus with heckles of 'sack the board' from shareholders.
Fans also displayed banners in protest at matches, plus were often heard chanting against the board and even disrupted games by throwing objects on to the pitch.
Lawwell - who oversaw a total of 38 trophy triumphs during his time in Glasgow - says the abuse and threats are now "intolerable".
Meanwhile, chief executive Michael Nicholson said "this is a sad day for Celtic" and major shareholder Dermot Desmond added that he was "very sorry to lose Peter" but understood his decision.
Your Site News' Gordon Duncan:
"It's a very complex situation at Celtic. From the outside, people probably look at a club that wins pretty much everything. Over the last couple of decades, they have won the most trophies here in Scotland, so people will wonder why there's so much unrest.
"However, there has always been this feeling amongst the Celtic supporters, or at least some of them, that the club should be doing more, they should try and build from a position of strength. Maybe they should spend more, maybe they should spend better, maybe they should strive more for European progress. We saw all this rear its head when Brendan Rodgers left, and this has been bubbling away and intensifying.
"We've seen 'sack the board' chants and banners, plus tennis ball protests disrupting games, so there is a level of unrest between some of the Celtic supporters and the board.
"Peter Lawwell used to be the CEO, he ran the club on a day-to-day basis. Since he's come back as chairman, I'm sure he would be keen to point out that he no longer runs the club on a day-to-day basis, and that is left to others.
"It has always felt like some Celtic fans either didn't quite believe that or didn't quite acknowledge that he was in a different role, and maybe believed that he still had more of an influence than he actually did. We'll never know behind closed doors."
Your Site' Chris Sutton:
"It's been a difficult season for Celtic on and off the field. For Peter to step down today after 21 years at the club which has been a really succesful period.
"In his statement, talking about the abuse he and his family have suffered. It isn't on.
"In many ways I feel really sad for him and his family that they had to put up with that level of abuse.
"It's a sad day for Peter Lawwell, who did so much for the club."
In a statement, Lawwell said: "It is with sadness that I announce my decision to stand down as chairman of Celtic FC.
"I believe that my 18 years as chief executive and three years as chairman at the club have shown my ability to meet and overcome challenges on many fronts, but abuse and threats from some sources have increased and are now intolerable.
"They have dismayed and alarmed my family. At this stage in my life, I don't need this. I cannot accept this and so I leave the club I have loved all my life.
"The motivations and aims of these detractors can be investigated by others. I prefer to look back on my career at Celtic with deep gratitude and satisfaction.
"My time at the club has brought joy to someone whose memories as a Celtic fan include standing as a schoolboy on the terraces as the European Cup was paraded at Celtic Park on that magical night in 1967.
"I have subsequently watched some great European nights at Paradise and am proud that the club has played group-stage football in all but two of the last 21 years while also enjoying domestic dominance.
"I also take great pleasure in the continuing and ever more substantial impact of Celtic FC Foundation. The club's foundation impacts so many lives in the Celtic Family and far beyond. We are more than a football club and the foundation is the most obvious evidence of this truth.
"Our achievements were all made possible by a dedicated workforce and a fervent support binding together. I am deeply proud and privileged to have been part of that.
"My life at the club has included dramatic ups and downs in football but they have also given me the experience, drive and desire which I will take on to my next project, whatever and wherever that may be.
"My thanks go to my many colleagues over the years who have supported me, and I am grateful to the coaches and players who delivered this era of remarkable and historic success."
Celtic's principal shareholder Dermot Desmond added: "I am personally very sorry to lose Peter as our chairman, but I understand and respect his decision, in light of recent events and what he has endured.
"I want to pay tribute to Peter for all he has given Celtic over so many years. As chief executive, Peter was the driving force of the club, and in his later role as chairman he oversaw board affairs.
"Peter has witnessed 38 cup or title triumphs in his time at the Club, a period of extraordinary domestic dominance for us as we have also competed in European football.
"Peter has also overseen the building of our training centre at Lennoxtown, the creation of the new facility at Barrowfield and the upgrading of Celtic Park, all of which were underpinned by the financial stability which has become the cornerstone of the club under his leadership. Celtic is in a strong position to withstand whatever the future may throw at us."
The club's chief executive, Michael Nicholson, who has also faced protests this season, said: "This is a sad day for Celtic. The abuse and threats directed towards Peter, and the impact on his family, are completely unacceptable. Such conduct will never be tolerated by the club.
"A lifelong supporter, with Celtic in his blood, Peter gave everything to the club, working tirelessly and standing up for the club with determination, passion and strength. Every decision he made was taken in the best interests of the club and our supporters."
