Banks were also hit by a denial of service attack shortly after the outage of the government pages, Ukraine's minister of digital transformation said.
Ukrainian authorities said this week they had seen online warnings that hackers were preparing to launch major attacks on government agencies, banks and the defense sector.
Ukraine has suffered a string of cyberattacks that Kyiv has blamed on Russia. However, Moscow, which is caught up in a mounting confrontation with the West over Ukraine, has denied any involvement.
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