The Blues face Nottingham Forest at Stamford Bridge on Saturday, before a trip to Manchester to face both United and City, with a final league game coming up at home to Newcastle.
Manchester City full-back Rico Lewis, also 18, has been kept back too due to his importance to Pep Guardiola’s side in their quest to win the treble.
Lewis is instead in line to make the England Under-21s squad for the first time during next month’s internationals.
Fellow 18-year-old talent Jamie Bynoe-Gittens was not released by Borussia Dortmund after deciding to have surgery on a persistent shoulder problem.
His selection may have been withheld anyway due to his first-team role in competing against Bayern Munich to win the Bundesliga.
A fourth player, Samuel Iling-Junior, has been blocked from leaving Juventus after netting a crucial goal against Atalanta in Serie A’s race for Champions League qualification.
The 19-year-old’s importance to the Italian giants is well known but they could yet cash in on him as a host of Premier League clubs line up to bring the ex-Chelsea academy prospect back to England.
England boss Foster had continued to work on calling up the quartet until the last possible moment, leading to the squad’s relatively late announcement.
Clubs like Chelsea, Arsenal, Tottenham and Liverpool have released a host of players to play for England.
Carney Chukwuemeka, Harvey Vale, Bashir Humphreys and Teddy Sharman-Lowe are among those travelling for the Blues, while Arsenal’s Brooke Norton-Cuffy is in the group alongside Tottenham’s Alfie Devine and Dane Scarlett.
Other star names due to feature at the tournament include Maximo Perrone, Manchester City’s Argentine midfielder, Chelsea’s exciting Brazilian talent Andrey Santos and the club’s United States goalkeeper Gabriel Slonina.
England will kick off their campaign on May 22 against Tunisia in the hastily rearranged tournament that was due to be played in Indonesia before being moved to Argentina.
The tournament will run until June 11 where the final will be played at Estadio Ciudad de La Plata in Buenos Aires.