The move is in line with the Islamic republic's efforts to set up a national intranet with no link whatsoever to the Internet that is available across the world.
Much to their dismay, Iranian netizens found that access to the search page of Google was only possible if one used an unsecured protocol.
An SMS regarding the new restrictions was sent to Iranian subscribers. The text message was as follows: "Due to the repeated demands of the people, Google and Gmail will be filtered nationwide. They will remain filtered until further notice."
Though the Google website did not mention the above curbs, many techies here had to resort to virtual private network (VPN) software to access their Gmail accounts.
Since censorship of online content is common in Iran, most of the professionals opt for VPNs to keep in touch with their acquaintances who are based in other countries.
In the past too, the Islamic republic had similarly blocked access to Google and Gmail. Restrictions were placed on both in the run-up to the parliamentary polls earlier this year.
Facebook and Twitter have been blocked several times. Besides cracking down often on these two popular social networking sites, censors routinely decide what sort of videos should be shared through YouTube by people in Iran.
As for the proposed walled-off intranet, an influential member of Iran's Parliament has averred that it is not intended as a replacement for the Internet.
"Cutting access to the Internet is not possible at all, because it would amount to imposing sanctions on ourselves, which would not be logical. However, the filtering will remain in place," said Mohammad Soleimani.