Josh Cullen will have a medical tomorrow after Anderlecht agreed a deal to sign the West Ham midfielder.
Cullen, 24, will sign a three-year deal with the Belgian side who are managed by former Manchester City captain Vincent Kompany.
Ireland international Cullen has come through the ranks at West Ham and will be the third academy product to leave the London Stadium this summer after Jeremy Ngakia and Grady Diangana.
West Ham midfielder Josh Cullen will have a medical at Belgian side Anderlecht tomorrow
Cullen will sign a three-year deal with former Manchester City captain Vincent Kompany's side
With less than a year left on his contract and David Moyes unable to guarantee Cullen the regular football he wants, the Hammers decided to accept Anderlecht's offer.
The move to Anderlecht will see Cullen secure consistent top-flight game time.
But, with his potential in mind, West Ham have included a 20 per cent sell-on clause and an option to match any future offers Anderlecht receive for Cullen in the deal.
Cullen made his West Ham debut in 2015 and has gone on to make 10 senior appearances for them, while enjoying successful loan spells at Bradford, Bolton and Charlton.
Cullen will join academy products Jeremy Ngakia (left) and Grady Diangana (right) in leaving
Hammers boss David Moyes was unable to guarantee Cullen the regular football he wants