Press Association Sport understands the Magpies have finally reached an agreement with the Ligue 1 side on a six-million-euro transfer after failing to land the player despite protracted talks during the summer.
The 27-year-old, a former team-mate of midfielder Yohan Cabaye, has made no secret of his desire to head for Tyneside, and a resolution to the long-running saga would come as a huge relief to manager Alan Pardew.
Sources in France have indicated that could now happen with the transfer window due to open on Tuesday.
It has been a difficult festive period for Pardew as the 51-year-old side saw his team score three times at Manchester United on Boxing Day and on a further three occasions at Arsenal on Saturday, yet leave empty-handed on both occasions having conceded a total of 11 times.
Newcastle's lack of depth has been cruelly exposed by injuries and suspensions in recent weeks and they headed for the Emirates Stadium with only one specialist central defender, skipper Fabricio Coloccini, with Steven Taylor on the long-term casualty list and Mike Williamson suspended.
They have little cover either at full-back, with Danny Simpson, who is out of contract at the end of the season and is yet to agree a new deal, and Davide Santon facing little genuine challenge for their places in the team.
Debuchy's addition to the squad would put a player of international quality at Pardew's disposal.
He appeared in all four of his country's games at the Euro 2012 finals in Poland and Ukraine last summer and now has 13 senior caps to his name.
Should the Magpies push home their interest in Debuchy, he is unlikely to be their last defensive target and they retain an interest in FC Twente's Douglas, a man they also chased last summer.