The Gunners will take on City away from home at the Etihad Stadium in the Premier League on Saturday evening.
Partey joined Arsenal from Spanish club Atletico Madrid on the final day of the summer transfer window.
The Ghana international midfielder was on international duty for the past two or so weeks, and the 27-year-old is now at the Gunners.
Arsenal manager Arteta has raved about the midfielder, and has said that he will be part of his squad for the game against City.
Arteta told Arsenal’s official website about Partey on Thursday: “Well he was here just yesterday, he is getting familiar with everything around the club.
“Today he will have his first training session, so everything has to come really quickly for him. We knew that before we signed him that he is fit, he is very willing to start playing and we will see how he goes in the next few days.
“I have seen the buzz around the place, the fans are really happy, I have seen some really positive reactions after we bought him, the same with the team, the squad and the staff.
“I think he is a player we had the radar on for a long time and we have managed to bring him in and I think he will be a really important addition to the team.
“He got to know some of his team-mates [already]. Not all of them, because some are still on international duty but we will have everyone back today and it will be a good day for him to get to know everyone.”