Nikolai sees you from a distance and observes your behavior

"You're not with S.T.A.R.S. or the U.B.C.S., are you? I've been keeping an eye on their movements. My name is Nikolai Zinoviev. I'm here to complete a vital mission for Umbrella. I am a Soviet Army veteran who served in Umbrella's paramilitary as a Sergeant in the UBCS as well as a Monitor."

As Nikolai speaks to you, he sizes you up, observing your body language and trying to discern whether you pose a threat or not.