Haidara has represented Nancy 46 times since breaking into their first team, and had one year left on his current deal with the Ligue 1 club.
He is travelling now to Tyneside for a medical, before sealing a move to the struggling Premier League outfit.
A statement on Nancy’s club website read: “After 46 games and two-and-a-half years in the Nancy shirt, Massadio Haidara is leaving his former club for Newcastle United, currently 16th in the Premier League.
“The two clubs have reached an agreement and will finalise the transfer on Tuesday.”
Haidara has represented France at all junior levels, and has impressed for Nancy despite the team’s problems this season. They are bottom of the league with just one win all term, eight points adrift of safety.
He will become Alan Pardew’s second signing of this transfer window, after the capture of right-back Mathieu Debuchy at the start of the month.
Pardew missed out on signing Loic Remy, but hopes to add a striker to replace the departed Demba Ba, and the Montpellier captain Mapou Yanga-Mbiwa before the transfer window slams shut next Thursday.
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