Jose Mourinho will leave Manchester United with immediate effect, the Premier League side announced on Tuesday.
A caretaker coach will be appointed until the end of the season, the club said, thanking the former manager for his work and wishing him success in the future.
"A new caretaker manager will be appointed until the end of the current season, while the club conducts a thorough recruitment process for a new, full-time manager," they said.
The Portuguese manager was at the club since 2016 where he replaced Louis van Gaal. He signed a three-year contract with the club, with the option to stay on until 2020.
Mourinho coached in the Premier League since 2004 when he joined Chelsea, later rejoining after five seasons at Inter Milan and Real Madrid.
He won three Premier League trophies in his career, a fact he reminded reporters of in a press conference after a bruising home defeat to Tottenham Hotspur by holding up three fingers, demanding respect.
Manchester United had an underwhelming start to the current season, but a 3-1 loss to league-leaders Liverpool on Sunday might have secured Mourinho's departure.
Earlier losses to Manchester City, Valencia and West Ham meant the club's season so far has not met expectations.
Mourinho has had a long list of excuses for his team's poor performance this season, saying "by the strategic and tactical point of view, we didn't lose," after Manchester United slumped to a 3-0 defeat to Spurs in August.
United currently sit sixth in the Premier League below Liverpool, Manchester City and Spurs.
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