Lukaku is understood to be closing in on a £97.5m return to Chelsea on a five-year deal, seeing him re-sign for the Blues after his ill-fated spell between 2011 and 2014.
The 28-year-old's departure would leave Lautaro Martinez, Alexis Sanchez and Andrea Pinamonti as Inter's premier forward options, with the former's proposed move to Arsenal all but ruled out as Lukaku edges closer to a move to Chelsea.
According to Marca, Inter have already got to work on identifying potential replacements and have created a three-man shortlist comprising Edin Dzeko, Duvan Zapata and Dusan Vlahovic.
The report adds that each member of the trio could be tempted by a move to the Scudetto winners, although Tottenham Hotspur are thought to be in contact with Vlahovic's camp over a move to North London.
Lukaku prepares to leave Inter after scoring 64 goals in 95 games for the Nerazzurri, and he also netted four times for Belgium at Euro 2020.