The 27-year-old Lille full-back travelled to the north-east after the Magpies and Lille agreed a fee, understood to be in the region of £5million, at the weekend.
However, with a medical to complete and personal terms to discuss, his transfer appears unlikely to be concluded until later in the week.
Debuchy has been in Newcastle's sights for some time, and manager Alan Pardew was hugely disappointed to miss out on one of his major targets after the two clubs were unable to reach agreement over him despite protracted negotiations during the summer.
However, with Danny Simpson having rejected the Magpies' latest contract offer with his current arrangement due to expire at the end of the campaign, the right-back position has become a priority.