Other companies that said they had been hit by a presumed cyber attack included Russian metal maker Evraz, French construction materials firm Saint Gobain and the world's biggest advertising agency, WPP - though it was not clear if their problems were caused by the same virus.
A massive cyberattack via a ransomware virus dubbed Petya has paralyzed dozens of businesses in Ukraine and neighboring Russian Federation, dpa cited state news agencies as reporting Tuesday.
Sistema said it plans to appeal against both the asset freeze and the ban on receiving dividend income.
The company later added it has notified law enforcement officials in connection with the cyber intrusion.
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The cyberattack targeted a number of oil, telecommunications and financial companies in Russian Federation and Ukraine, blocking computers and demanding 300 US dollars in bitcoins, Group-IB told Russia's Prime news agency.
"Neither the production process, nor mining and preparation of oil were stopped", the company said on Twitter.
Analysts said three of every four USA oil and gas companies experienced a cyber-attack in 2016, but only a few firms said the computerized attacks posed a major security risk.
The Ukrainian prime minister called the attack "unprecedented" but said that "vital systems haven't been affected".
"As a result of these cyber attacks these banks are having difficulties with client services and carrying out banking operations", the central bank said in a statement.