I usually pick a phone that addresses to my collogues who is not in the office for 5 or 10 mins. They probably go to the other departments and will come back soon. I usually tell that "He is out of the office and will be back soon". The callers sometimes misunderstood. So, they ask me "Is he on annual leave?".
Could someone please tell me what is the best way to say in that situation?
Thanks