Ukraine's state security service SBU and the state-run Computer Emergency Response Team (CERT) said the attack could take place Oct. 13-17 when Ukraine celebrates Defender of Ukraine Day, Reuters wrote.

Read alsoU.S. offers $5 mln to help Ukraine boost cybersecurityUkraine, which believes Russia is behind regular attacks on its computer systems, is trying to roll out a national strategy to keep state institutions and major companies safe. Moscow denies that it is behind cyber attacks on its neighbor.

The security agencies said that a new attack may be similar to the NotPetya computer virus which struck on June 27 taking down computers in Ukrainian government agencies and businesses before spreading rapidly through corporate networks of multinationals with operations or suppliers in eastern Europe.