The 21-year-old Belgian starlet arrived from Genk last summer in a £6.7million deal before moving to Bundesliga side Werder Bremen on a season-long loan.
And after a string of impressive performances for the Weserstadion outfit, his agent has told him that the west Londoners want to keep him, despite interest from Bremen, Borussia Dortmund and Bayer Leverkusen.
Agent Patrick De Koster has held talks with Chelsea and said: "The conversation was very positive. They are pleased with his progress and think he is ready to become part of the first team.
"The only problem is there is still no clarity about who is head coach next season."