Ukraine ordered the blocking of access to a number of Russian websites Tuesday in the latest round of sanctions since Russia annexed Crimea in 2014.
President Petro Poroshenko's office announced the decree, which he signed a day earlier, banning operations of popular Russian websites, such as search engine Yandex, for three years.
The listed websites were still functioning in Ukraine Tuesday, and it is unclear how and when the government plans to block them.
The Ukrainian government cited security concerns, saying the ban was imposed partly to protect against companies "whose activities threaten the information and cyber security of Ukraine," according to a statement released by the Security and Defense Council.
The latest round of sanctions adds Yandex and social media sites Odnoklassniki and Vkontakte to the list of over 400 Russian firms blacklisted by Kyiv since Moscow's annexation of Crimea and consequent pro-Russian separatist uprising in 2014. According to the Reuters news agency, the Kremlin has threatened retaliation.