The Belgium international struggled in his first season back at Stamford Bridge following his £97.5 million move from Inter last August.
Lukaku scored 15 goals in 44 appearances for Chelsea last term and angered the club in December with his interview to Italian media in which he admitted he was unhappy with his situation under Thomas Tuchel.
The 29-year-old also made it clear that he would be keen to return to Inter and the striker has now got his wish.
According to The Athletic, Chelsea and Inter have agreed an €8 million (£6.8m) loan fee plus add-ons to pave the way for Lukaku’s return to San Siro.
It’s also understood that Lukaku has agreed a salary cut in order to secure his loan.
Lukaku is due to undergo next week ahead of his move back to Serie A.
In December, Lukaku told Sky Sports Italy: ‘I really hope in the depths of my heart to return to Inter, not at the end of my career, but at a still good level to hopefully win more.’
Before his move to Chelsea, Lukaku played a key role in helping Inter win the Serie A title under Antonio Conte.
Thomas Tuchel, meanwhile, was hoping to keep Lukaku but the striker was intent on moving back to Italy.
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