The Blues have been linked with a swoop to sign the Wales international from the Champions League winners this summer.
Bale came off the bench to score twice in Real Madrid’s 3-1 win against Liverpool FC in the Champions League final.
The Welsh forward has struggled to hold down a regular starting spot under Zinedine Zidane in the 2017-18 season.
Bale appeared to open the door to a potential return to the Premier League following the Champions League showpiece.
Real Madrid have been regularly linked with Chelsea FC number 10 Eden Hazard but a deal hasn’t materialised so far.
However, reporter Castles has poured cold water on talk of a potential deal to sign Bale in the summer transfer window.
“Chelsea can’t afford the move,” Castles told the Transfer Talk podcast. “Unless Madrid are prepared to subsidies the sale of their world record signing.
“I don’t see a club like Chelsea in their current financial situation to be able to take it.”
Chelsea FC finished in fifth place in the Premier League last season to miss out on the Champions League spot.
The Blues won the FA Cup crown thanks to a 1-0 win against Manchester United at Wembley last month.
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