The Toffees centre-half is one of England’s brightest prospects after Stones broke into the first-team at Goodison Park under the guidance of current Everton manager Roberto Martinez.
The market has no rules or limits from season to season
Manchester United have also been linked with a move for the highly-rated 21-year-old as Louis van Gaal looks to bolster his options at centre-half ahead of the new season.
And Mourinho, who led Chelsea to their fourth Premier League title last season, accepted that it was up to the Blues whether they wanted to meet Stones’s reported £30m price tag.
“That is the market now,” Mourinho is quoted as saying by talkSPORT.
“You only pay it if you want to. If you don’t want to pay it, don’t pay. It’s as simple as that.
“The market has no rules or limits from season to season.”
Stone was a key part of Matinez’s Everton defence last season as the centre-half scored one goal in 28 games in all competitions last season.
The Toffees youngster has three-and-a-half years remaining on his current deal after he moved to Everton from Barnsley in a £3m deal in 2013.
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