The Southampton-born player came through the academy ranks at Chelsea, joining the club at the age of eight, before being sent on loan to Brighton & Hove Albion for the 2022–23 season.

He made 22 appearances for Roberto De Zerbi's (44) side in all competitions and helped Brighton qualify for European football for the first time in the club's history.

"It's always been an easy decision," Colwill said in a statement.

"As I've grown up, all I've known is Chelsea. I've spoken with the manager and he's given me reassurance, that trust I needed. He's spoken with me not just as a player but a person. It's made a big difference."

Colwill helped England clinch the Under-21 European Championship last month and was part of the defence that did not concede a single goal before being named in the team of the tournament by UEFA.

The highly-rated youngster was linked with a move to several European clubs before extending his stay at Chelsea.

"Levi is an outstanding player who has risen to every challenge in his career so far. We are thrilled he will remain at Chelsea for years to come," Chelsea's co-sporting directors Laurence Stewart and Paul Winstanley said in a joint statement.

Chelsea are looking to revive their fortunes under former Tottenham Hotspur manager Mauricio Pochettino (51) after languishing in 12th place in the last campaign, their worst finish since 1994.