Inter Milan have warned Chelsea that it would take an offer of more than €100m to tempt them to sell Romelu Lukaku, according to Sky Sports.
The Blues are keen on re-signing their former striker, as Thomas Tuchel looks to bolster his front line ahead of his first full season in charge.
Chelsea sold the 28-year-old to Everton for £28m in July 2014. He was close to a return in July 2017, before eventually joined Manchester United for £75m.
Inter signed him from United for £73m two years ago.
Lukaku played a key role in Inter's Serie A triumph last season, netting 24 goals.
The Serie A side need to reduce their wage bill and Antonio Conte left the club after winning the league title amid concerns about plans to cut his budget.
However, Lukaku is very happy at the San Siro and ready to give his all next season.
Chelsea are determined to sign a world-class striker and their other main target this summer has been Borussia Dortmund's Erling Haaland.