Co studio head Patrick Kelly has also said Infinity Ward is currently playtesting four and five-player squads.
Warzone launched on Tuesday with two 150-player game modes, Battle Royale and Plunder.
“I can tell you we are already playing with 200 players,” Kelly told USA Today. “We are going to release that a little bit later.”
The game is currently playable solo or as a duo or a trio, but the options are likely to be expanded.
“So let’s say you show up alone and just want to play solo … or if you show up with a buddy, you just check the box that says, ‘Don’t fill my squad,’ and you will just be a duo,” Kelly said.
“I can tell you we have four- and five-player squads we are already playing with. But we want to launch with something we know works really well and we have tested to the nines and then play around with these different team sizes.”
Update March 17: A new Call of Duty Warzone update has introduced a Solos option for the game’s Battle Royale mode.
Original story continues: Kelly also said new game modes are being worked on. “We want this to be continuously emerging, and we want it to be something that really continuously surprises and delights players.”
Call of Duty Warzone attracted six million players in its first 24 hours, according to publisher Activision.
For more on the game, see our Call of Duty Warzone Tips: 19 things you didn’t know feature.