Napoli have allegedly told Chelsea that they must double their offer of £3.5m to have any chance of landing Maurizio Sarri as their next manager.
The Italian club's president Aurelio De Laurentiis is aiming to recoup the head coach's full release clause, which expires at the end of May, from the Blues, according to The Sun.
Sarri is under contract with Napoli until 2020, but the club has already confirmed that he will be replaced by Carlo Ancelotti for next season.
Chelsea, meanwhile, are yet to announce the departure of their current manager Antonio Conte, who is widely expected to leave the club this summer.
Conte won the Premier League title and the FA Cup during his two seasons in charge at Stamford Bridge, but is odds-on to be replaced by Sarri.
