The Naples club's president Aurelio De Laurentiis had been quoted as saying that the 53-year-old's capture was complete on Friday. 

However, he has since told Sky Sport Italia: "I closed the deal for the new coach, but I can not announce it officially until I get a release from the other company (with) which (he) is under contract until June 30."

Benitez's last permanent managerial role also came in Italy, but the Spaniard was sacked after just six months in charge of Inter in 2010.

The former Liverpool boss was appointed by Chelsea on an interim basis in November 2012 and led the London club to success in the UEFA Europa League as well as a third-placed finish in the Premier League.