Chelsea have reportedly been told that it will take £30m to sign Middlesbrough centre-back Ben Gibson.
The Premier League leaders have been consistently linked with a move for Gibson over the last couple of months, and it is understood that scouts from the Blues have watched the defender on a regular basis this season.
Middlesbrough managed to resist interest in the January transfer window, but it is believed that Chelsea boss Antonio Conte has made Gibson his top defensive target for this summer.
According to The Express, Middlesbrough are prepared to sell the 24-year-old, but will demand that Chelsea pay £30m for a player that only signed a new five-year contract at the Riverside Stadium in 2016.
Gibson, who came through the youth system at his current club, has started all 27 of Middlesbrough's Premier League games this season.