The Evening Chronicle says several clubs, including Arsenal, Manchester City and local rivals Sunderland, have been linked with the 22-year-old Frenchman, who is desperate to stay in the Premier League.
But Spurs are the only would-be buyers to have expressed a firm interest in doing a deal with Newcastle at the price they want.
Tottenham boss Harry Redknapp sees central defence as the area of his squad now most in need of strengthening, with the fitness of first-choice duo Ledley King and Jonathan Woodgate an almost constant concern.
"We're waiting to hear back from a couple of other clubs regarding Seb, but Tottenham are definitely keen," said a source close to Bassong.
"It's still early days, but we do expect things to be resolved quite quickly once teams report back for pre-season."