Iran's ICT minster Mahmoud Vaezi says his ministry is studying the possible launch of Telegram calls in Iran. Telegram, the most popular messaging app in the country with millions of users, launched its Over-the-Top (OTT) voice calling service on 30 March in Western Europe, but the service is yet to be launched in Iran and other Asian states, ICTNA reported. Since OTT players do not require any business or technology affiliations with network operators for providing such services, they are often known by the term OTT applications.
Source: https://www.telecompaper.com/news/iran-mulls-launch-calls-from-telegram-messaging-app--1191538