Newcastle have been long-term admirers of the attacking midfielder, and appeared to have reached an agreement to sign him back in January.
That prospective deal fell through, but the Premier League club finally look to have secured the 24-year-old's services.
"There is an agreement with Newcastle," Nicollin is quoted as saying by the French media.
Cabella has established himself as one of the top young players in France in recent years with his exciting performances for Montpellier.
The Corsican-born playmaker was called into France's Fifa World Cup squad after injuries to Franck Ribery and Clement Grenier, but did not make an appearance for Didier Deschamps' side in Brazil.
A Ligue 1 title winner with Montpellier in 2011-12, Cabella scored 14 goals for Rolland Courbis' men last term as the struggled to a 15th place finish.
His prospective move to Newcastle, believed to be worth approximately £13million, will see him become the Tyneside club's fourth signing of the close-season following the arrivals of Ayoze Perez, Jack Colback and Siem de Jong.