American media conglomerate Comcast, which owns NBC Universal, issued a statement revealing that it had "mutually agreed" that Shell should depart his role with immediate effect.

The decision comes after the company was part of a three-party investigation into a complaint of misconduct levelled against Shell.

Shell, who joined Comcast in 2004 and was appointed chief executive of NBC Universal in January 2020, apologised to colleagues following his ousting.

"Today is my last day as chief executive of NBCUniversal," said Shell.

"I had an inappropriate relationship with a woman in the company, which I deeply regret.

"I'm truly sorry I let my Comcast and NBCUniversal colleagues down, they are the most talented people in the business and the opportunity to work with them the last 19 years has been a privilege."

NBCUniversal bought US broadcasting rights to the Olympic Games between 2021 and 2032 for $7.65 billion (£6.1 billion/€6.9 billion) in 2014.

A replacement for Shell has yet to be announced with fewer than 500 days to go before NBCUniversal is due to broadcast next year’s Olympics in Paris.

Comcast President Mike Cavanagh and chief executive Brian Roberts also released a statement as reported by Varity Magazine.

"We are disappointed to share this news with you," said Cavanagh and Roberts.

"We built this company on a culture of integrity.

"Nothing is more important than how we treat each other.

"You should count on your leaders to create a safe and respectful workplace.

"When our principles and policies are violated, we will always move quickly to take appropriate action, as we have done here.

"Please know that NBCUniversal is performing extremely well operationally and financially, and we couldn’t be more enthusiastic about our position and prospects going forward. 

"We are fortunate to have an experienced, world-class group of executives leading this incredible company."