Carlo Ancelotti has quit his role as Everton manager to take over at Real Madrid.
Ancelotti, who joined Everton on a four-and-a-half-year contract in December 2019, replaces Zinedine Zidane in the Spanish capital.
The 61-year-old Italian, who previously managed Real between 2013 and 2015, guiding the club to a 10th European title, has agreed a three-year contract.
Zidane resigned last week following Real’s failure to win a trophy last season.
Ancelotti told Everton’s website: “I would like to thank the board of directors, the players, and the Evertonians for the tremendous support they have all given me during my time at the club.
“I have complete respect for everyone associated with Everton and hope they can achieve the exciting opportunities they have in front of them.
“While I have enjoyed being at Everton I have been presented with an unexpected opportunity which I believe is the right move for me and my family at this time.”
Ancelotti guided Everton to a 10th-placed finish last season and now leaves them looking for a sixth permanent boss in five years.
The Merseyside club said: “Everton would like to place on record its thanks to Carlo for his service to the club over the past 18 months.
“The club will begin the process of appointing a new manager immediately and will provide updates in due course.”
David Moyes has already been linked with a return to Everton, but the PA news agency understands he is still close to signing a new three-year contract with West Ham.
Moyes, who guided the Hammers into next season’s Europa League, has already triggered a one-year contract extension.
Real said Ancelotti will be presented to the media at 6pm local time on Wednesday.