Telegram was open and working in Iran without any VPN or other circumvention methods in May 2015.[36] In August 2015, the Iranian Ministry of ICT asserted that Telegram had agreed to restrict some of its bots and sticker packs in Iran at the request of the Iranian government.[37] According to an article published on Global Voices, these features were being used by Iranians to "share satirical comments about the Iranian government". The article also noted that "some users are concerned that Telegram's willingness to comply with Iranian government requests might mean future complicity with other Iranian government censorship, or even allow government access to Telegram's data on Iranian users".[37] Telegram has stated that all Telegram chats are private territory and that they do not process any requests related to them. Only requests regarding public content (bots and sticker packs) will be processed.[38] In May 2016, the Iranian government asked all messaging apps, including Telegram, to move all Iranian users' data to Iranian servers.[39] On 20 April 2017, the Iranian government completely blocked Telegram's new voice calls, a service that allows individuals to make calls via secure, end-to-end encryption, and keep their conversations private.[40]Mahmoud Vaezi Chief of Staff of the President of Iran said reason for blocking Telegram free voice calls is so Iranian corporations keep revenue from voice calls.[41]