Tottenham manager Roberto De Zerbi refused to say if Richarlison would remain with the club after reports that the Brazil striker wants to end his contract.
Richarlison is reportedly in a dispute with Tottenham over the remaining nine months on his current deal.
The 29-year-old was linked with a move to his former club Everton, but the deal collapsed just before the September 1 transfer deadline in the Premier League.
Richarlison is reported to want Tottenham to agree a loan switch that would allow him to join Brazilian side Vasco da Gama before reassessing his options in January.
Vasco da Gama director of football Admar Lopes has confirmed they are in talks about a move for Richarlison.
But Tottenham are believed to prefer a permanent sale, leaving the situation at an impasse as the Brazilian transfer window is closing on Friday evening.
Richarlison, who joined the north London side in 2022, hasn't played for Tottenham since their 3-0 defeat at Brentford on the opening weekend of the Premier League season.
He was left out of Tottenham's official 25-man squad for the top-flight campaign when it was announced on September 3.
Asked if Richarlison had a future at the club, De Zerbi told reporters on Friday: "I don't know. It's not my job.
"What I can say is I know very well what the club has done for Richarlison and I know very well what Richarlison has done for the club in the last month, two months.
"I know, the club knows, he knows, his agent knows. Everyone knows better than you (the media). Much better."
With Richarlison in exile, Tottenham are winless in the Premier League this season and still waiting for their first top-flight goal ahead of Saturday's visit from Everton.
"I think we are better than last season," De Zerbi said. "It's difficult to believe right now because we are not winning, we are not scoring, but I'm positive.
"I believe in my players, I believe in this group of players. I think the players have big qualities, big potential, and now I'm positive."