The Frenchman is set to join on loan for the coming season, according to the report, with a mandatory purchase option next summer that will amount to a £14.2 million total transfer fee, with Imbula set to sign a four-year deal.
Spurs were also linked with a move for another of France's most promising young midfielders, Geoffrey Kondogbia, this summer, along with Arsenal, but the Monaco man elected to join Inter.
And it looks like the Nerazzurri have pulled off another superb signing with Imbula's impending arrival.
Imbula's stock rose significantly last season as Marseille set the early pace in Ligue 1, playing 39 times and scoring two goals in Ligue 1 this season.
Both Spurs and Southampton are expecting departures from their midfields this summer, with Paulinho set to leave White Hart Lane and Schneiderlin expected to leave St Mary's.