The France Under-21 international is set to become the club’s seventh major summer acquisition.

Olise, who was born in London, had 11 Premier League assists for Palace last season and signed a five-year contract with the Eagles in 2021.

Olise, 21, was a Chelsea youth system member before departing at the age of 14.

He is currently rehabilitating from a hamstring injury sustained while representing France in the European Under-21 Championship.

The winger had an outstanding 2022-23 season with Palace, recording 11 assists and scoring two goals in 37 games and was awarded the club’s player of the year.

Olise would be one of eight senior signings at Stamford Bridge this summer, led by the signing of Ecuador midfielder Moises Caicedo from Brighton for a cost of £100 million, which could grow to a British club record of £115 million.

The London club now includes Axel Disasi, Christopher Nkunku, Nicolas Jackson, Lesley Ugochukwu, Angelo Gabriel, Robert Sanchez, and Diego Moreira.

Caicedo is Chelsea’s 22nd fee-paying signing since American investor Todd Boehly and his Clearlake group took over in May 2022, bringing the new owners’ total outlay to nearly £900 million.

Mauricio Pochettino, the new manager of Chelsea, has been entrusted with rebuilding the roster and dramatically improving on last season’s 12th-place result in the Premier League.

This summer has seen the departures of Mateo Kovacic, Edouard Mendy, Kalidou Koulibaly, N’Golo Kante, Mason Mount, Kai Havertz, Christian Pulisic, Ruben Loftus-Cheek, Ethan Ampadu, Pierre Emerick-Aubameyang, Abdul Rahman Baba, and former captain Cesar Azpilicueta.

Chelsea began their Premier League campaign with a 1-1 draw at home against Liverpool last Sunday.