Lukaku, 29, endured a tough 2021-22 season following his €115 million move to Stamford Bridge from Inter last summer, scoring eight goals in 26 Premier League appearances.
His time at Chelsea was further hampered by controversy following an interview with Sky Sports Italia in which he stated he was “not happy” with the system that manager Thomas Tuchel was using.
The Belgium international returns to Inter, whom he helped secure the Serie A title in 2021 by scoring 24 times and assisting a further 10 in 36 matches in their league campaign.
— Inter (@Inter) June 29, 2022
Sources told ESPN that Chelsea had originally demanded a loan fee of around €20m for Lukaku but eventually accepted a structured deal totalling around €12m including bonuses.
Sources also added that Inter will also cover the striker’s £300,000-a-week wage.
Lukaku struggled to break into the first team during his first stint with Chelsea which ended in 2014.
ESPN’s James Olley also contributed to this report.