These malfunctions come as Ukraine’s deputy prime minister announced a “cyber attack” on Russia in response to similar attacks.
Several Ukrainian government websites, including the government website and the Ministry of Foreign Affairs website, were down last week.
Ukrainian authorities said they had detected online warnings that hackers were preparing to launch major attacks on government agencies, banks and the defense sector.
Ukraine has suffered a series of cyber attacks that Kiev has blamed on Russia. Moscow denies involvement in the attacks.