The 27-year-old Lille full-back came close to joining the Magpies last summer but a deal failed to materialise.
However, the two clubs have now agreed a fee, with the French defender set to discuss personal terms and undergo a medical with the Premier League outfit.
“Signing Mathieu Debuchy is just a question of the medical really,” said Pardew after watching his side lose 2-1 to Everton at home on Wednesday night.
“He has quality and experience and that is what we missed tonight. Those key moments are costing us.”
The Newcastle United boss added: “[The] Demba Ba [transfer saga] has been hanging over us but we have drawn a line under it now. For us it’s about bringing someone else in and we are working on that now.”
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