Dummett this week signed a new one-year deal at the club ahead of the expiry of his contract in the summer.
The 30-year-old defender impressed Howe after returning to full fitness, having missed much of last year through injury.
Asked why he was so keen to keep Dummett at the club, United’s head coach said: “Great, great personality, Newcastle through and through. Loves the club, loves everything connected with the club. I still think he’s got a lot to offer on the pitch.”
Longstaff – whose deal expires at the end of the season – has been involved in protracted talks over a new contract, and Howe issued an update on discussions ahead of Sunday’s game against Manchester City.
“I hope we can get a positive resolution with Sean,” said Howe. “Hopefully, that one’s moving quite well – and in the right direction. But, obviously, until he’s signed the contract, I can’t say for definite.”
The midfielder signed his present deal before he made his Premier League debut, and addressed his future last month.
The 24-year-old said: “With the position we’ve been in, if I’m there sitting and sulking and worrying about me and not about the team, that puts the team at a disadvantage,” said Longstaff.
“That’s not the right thing to do. Now we’re sort of safe, I can maybe put a little thought into it and what’s going to happen.”
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