"We have heard from users in Iran that they are having trouble accessing Gmail," Google said in a statement.
"We can confirm a sharp drop in traffic and we have looked at our own networks and found that they are working properly," the Internet giant said.
"Whenever we encounter blocks in our services we try to resolve them as quickly as possible because we strongly believe that people everywhere should have the ability to communicate freely online," Google said.
"Sadly, sometimes it is not within our control."
Google's statement came after The Wall Street Journal reported that Iran's telecommunications agency had announced a permanent suspension of Gmail and planned to roll out a national email service for Iranian citizens.
