"It has been a privilege to serve as the Chief Executive Officer of the International Cricket Council," Allardice said. "I am incredibly proud of the results we have achieved, from enhancing the global reach of cricket to the commercial foundation put in place for ICC Members.

"I'd like to thank the ICC Chair, the board of directors and [the] entire cricket community for their support and collaboration over the past 13 years. I believe this is the right time for me to step down and pursue new challenges. I am confident that cricket has exciting times ahead, and I wish the ICC and the global cricket community every success in the future."

"On behalf of the ICC Board, I want to sincerely thank Geoff for his leadership and commitment during his tenure as Chief Executive," Shah said. "His efforts have played a key role in advancing cricket globally. We are truly grateful for his service and wish him all the very best in his future endeavours."

Allardice, like his predecessor Dave Richardson, maintained a lower profile as CEO than predecessors such as Haroon Lorgat or Malcolm Speed, but he was an instrumental administrator within the ICC. In particular, during his stint as general manager cricket he can claim some significant achievements: overcoming the BCCI's early concerns with DRS and ensuring it was implemented as standard across the international game; standardising and implementing the processes around illegal actions; overseeing the creation of the World Test Championship and the (now-defunct) ODI Super League as a means of bringing context to bilateral cricket. In an era in which domestic, cash-rich T20 leagues mushroomed, the latter was an important addition.

When he took over as CEO in an interim capacity, it was thought he had done so with some reluctance. And when he took on the role permanently, it was at a difficult time for the game, navigating its way through the end of the Covid-19 pandemic. But one of his major achievements as CEO was to get cricket into the Olympic Games, which could have a lasting consequence for the growth of the game. Overseeing a first ICC world event in the USA - the T20 World Cup last year - should have been a similarly seminal moment in the growth of the game, but the operations of that tournament have become the subject of an audit since, and board members have expressed unhappiness with the way it was run.

The ICC said in a statement that its board will "initiate the next steps to identify" Allardice's successor, but it has not clarified if Allardice was leaving with immediate effect or whether he will stay until the end of the Champions Trophy in February-March.

Allardice is the latest in a spate of departures of senior ICC management, following the exits of Alex Marshall (the anti-corruption head), Chris Tetley (head of events) and Claire Furlong (general manager marketing and communication) in recent months.