The out-of-favour playmaker looks to be on the verge of a return to the Bundesliga, thought to be initially on loan with a view to a permanent deal in the summer
The Belgium international spent 2012-13 on loan in the Bundesliga with Werder Bremen - scoring 10 goals in 33 appearances - but has featured just three times under Jose Mourinho this season.
The 22-year-old was forced to train with Chelsea's youth side after Mourinho criticised his effort and the Portuguese confirmed on Saturday that bids had been made for his services.
And Wolfsburg look primed to take advantage with general manager Klaus Allofs expressing his belief that a deal is close.
He told Wolfsburger Nachrichten: "It's not that we can confirm the deal just yet, but we are no longer so far apart with Chelsea that we can't bridge the differences."
Wolfsburg enjoyed a strong first half to their Bundesliga campaign and will resume their season sat fifth in the German top flight, two points off Borussia Dortmund in fourth.
They will get back to competitive action with a home game against Hannover on January 25.