"We've had many chats and no one is more disappointed than he is," Jones told British media at the end of a two-day training camp in Brighton on Tuesday.
"He is a proud Northampton player and he wants to captain England. That's the first mistake he has made for us. Dylan made a judgment error."
Jones has set strict fitness targets for the 30-year-old to meet before the squad reconvene on Jan. 22 for a pre-tournament camp in Portugal.
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"Dylan has got to come to Portugal fit and ready to go," Jones said. "He's doing all the right things at the moment and if he keeps on doing that, there's no reason why he won't be starting hooker and captain."
England will face France at London's Twickenham Stadium on Feb. 4 in their opening game of the tournament.
(Reporting by Hardik Vyas in Bengaluru; editing by Sudipto Ganguly)
