Conte fears Spurs could be derailed by 'big difficulty' with injuries
The winger was expected back this month after suffering a hamstring problem while playing for Sweden.
But Conte revealed on Friday that the 22-year-old winger now faces a race against time to be fit before the Premier League pauses on November 13 ahead of the World Cup in Qatar.
Kulusevski has not played for Tottenham since September 17, while Brazil forward Richarlison is also sidelined with a calf strain that is expected to keep him out until November.
"Deki Kulusevski is not available. I think we have to wait a bit of time to see him with us," Conte said ahead of Sunday's clash with Newcastle.
"Yeah (I am worried) because his recovery was going well and then one day the situation worsened.
"We have the medical department to face injury situations and they have to solve the situation in a short period because you know if you are good to solve the situation in a short period, it means points in the table."
Tottenham's injury woes in the attacking department have left Conte heavily reliant on Harry Kane and Son Heung-min, with Lucas Moura only recently back after a long-term calf problem.
Conte's side are third in the Premier League but lost 2-0 at Manchester United on Wednesday after a lacklustre display that cried out for the kind of invention provided by Kulusevski and Richarlison.
Acknowledging that injuries could hamper Tottenham's hopes of finishing in the top four and progressing in the Champions League, Conte said: "For sure this type of situation creates a big, big difficulty.
"For me, also fingers crossed because at the moment we have Harry and Sonny in good health. I hope they continue to stay that way or I'll have to think about putting my shoes on to play.
"Now to complain, I think it's not right or fair. When you go to play Champions League, especially if you play in the Premier League, you have to know that you're going to have a difficult season for injuries, for massive games, for players who become tired.
"Sometimes you can give rest, sometimes you have to force the situation and risk injuries. This situation is part of the process for a club like Tottenham."
