The Chelsea summer signing has picked up a calf injury and will be forced to sit on the sidelines until the middle of next month.
Conte has ruled Drinkwater out until after the next international break.
The Blues forked out £35m on deadline day to bring the midfielder to Stamford Bridge.
And he'll be disappointed to see the start of his life at Chelsea delayed by injury.
Conte said: "He had a muscular problem in his calf.
"I think it’s very difficult to see him before the international break.
"He needs time to recover.
“It’s a pity because he was starting to work and to improve his physical condition.
“Now we have to move all these situations.
"And in two, three weeks, four weeks, I don’t know.”
