Lukaku re-joined the club just five months ago in a £97.5 million from Inter Milan.
The interview has been released just a day after the Belgian scored in a 1-1 draw with Brighton.
He told Sky Sport, per Fabrizio Romano: “Physically I am fine. But I’m NOT happy with the situation at Chelsea. Tuchel has chosen to play with another system – I won’t give up, I’ll be professional. I am not happy with the situation but I am professional – and I can’t give up now”
As well as revealing his unhappiness at the west London club, he also spoke of his desire to return to Inter at some point in his career.
He continued, per Romano: “Now it’s the right time to share my feelings. I have always said that I have Inter in my heart: I know I will return to Inter, I really hope so. I am in love with Italy, this is right moment to talk and let people know what really happened.
“I really hope from bottom of my heart to return to Inter not at the end of my career, but when I’m still at top level to win more together.
“I want apologise to the Inter fan, timing of my words was wrong: what you did for me will remain forever”.
Lukaku joined Inter in 2019, scoring 64 times in 95 games for the Italian giants.
The 28-year-old has had some bad luck with injuries and fitness since returning to Chelsea in the summer.
He has scored six times in 17 games for Chelsea this campaign. Lukaku’s future at the club is now unclear.
It goes without saying that Tuchel will not be too impressed with his star striker’s comments.