The 23-year-old’s deal at Toulouse expires at the end of the season and he is free to sign a pre-contract agreement from January 1.
Sissoko is believed to have already committed himself to the Toon despite interest from Spurs, Liverpool, Everton and Fulham.
If indeed the Magpies have won the race to sign highly rated Toulouse midfielder Moussa Sissoko then there may be some who believe this could lead to the departure of Cheik Tioté or Yohan Cabaye.
Tioté is a target of Chelsea, and Arsenal want Cabaye.
Neither player has shown any desire to leave St James' Park, both pledging their future to the Magpies.
But Derek Llambias has told the media "every player has his price at Newcastle".
Sissoko is a box to box midfielder who has been targeted by many of Europe’s ‘Elite’ and Alan Pardew would struggle to find room for the French international unless he was considering his position on either Tiote or Cabaye.
As well as getting Cabaye, Newcastle have brought in Romain Amalfitano, Mehdi Abeid and Sylvain Marveaux from Ligue 1.