The Basel defender was heavily linked with the Gunners on a number of occasions over the latter half of last season, with rumours having suggested that Arsene Wenger saw the Swiss ace as summer target.
However their interest has not yet formalised itself, and now Spurs are lurking.
Mauricio Pochettino is said to have his eye on backline additions in the coming months as he plots to rebuild his inherited Lilywhites squad for a genuine top four push.
It is understood that the Argentine wants to assess the centre-back while he’s on World Cup duty, and if impressed a £9m offer could be made.
Schar was a surprise exclusion from Switzerland’s XI for their opening game against Ecuador, but he is still seen as a valued member of their 23-man squad.
The 22-year-old was a key man for Basel last term, impressing during their Champions League run.
Schar only joined his current club in 2012, but is already a fans’ favourite at St. Jakob-Park.