The League One leaders are desperate to keep the striker at Elland Road and will do all they can to fend off any interest in his services over the New Year.
Beckford is in the final year of his contract with the Whites, having rejected new terms last summer, and is set to become a free agent at the end of the season.
Newcastle have been interested in the 25-year-old for some time now, going back to Kevin Keegan's time in the hotseat. And both Joe Kinnear and Chris Hughton made it known to Mike Ashley they wanted him at St James' Park.
Simon Grayson: "The chairman has promised he'll go on supporting my decision from the summer that Jermaine will stay until the end of the season no matter what.
"The January window will make no difference.
"If he leaves on a free after winning us promotion then that's our sole aim - if he decides to sign a new deal in the meantime, then so much the better."