Ukraine said Sunday it had evidence Russia was behind a massive cyberattack that knocked out key government websites this past week, AFP reported.

"All the evidence points to Russia being behind the cyberattack," the Ukrainian digital transformation ministry said in a statement.

Kremlin spokesperson Dmitry Peskov said Russia was not related to the cyberattack on Ukrainian government websites during an interview with CNN.

Ukraine's foreign ministry said on Friday that, due to a massive cyberattack, the websites of the ministry and a number of other government agencies are temporarily down.