"As a result of a massive cyber attack, the websites of the Ministry of Foreign Affairs and a number of other government agencies are temporarily down," the spokesman for the foreign ministry said.

"Our specialists are already working on restoring the work of IT systems, and the cyber police opened an investigation."

Asked whether Russia was suspected as being behind the attack, the spokesman said: "It's too early to draw conclusions, but there is a long record of Russian assaults against Ukraine."

Reuters has reported that as well as the website of the ministry of foreign affairs, the cabinet of ministers, agrarian policy, security and defence council and the ministry of education all appeared to also be not working.

"Due to the global attack on the night of Jan. 13-14, 2022, the official website of the Ministry of Education and Science is
temporarily down," the ministry said on Facebook.

On some of the websites there is a text in three languages - Ukrainian, Polish and Russian - saying all data of Ukrainians uploaded to the network had become public.

"Ukrainian! All your personal data was uploaded to the public network. All data on the computer is destroyed, it is impossible to restore it.

"All information about you has become public, be afraid and expect the worst. This is for your past, present and future,"
the message reads.

Russia has repeatedly been accused of cyber attacks against Ukraine, including far more serious cyber assaults such as targeting critical national infrastructure such as power.

Cyber attacks against websites are a much less sophisticated and less harmful form of attack.

Russian cyber attacks accompanied Russian military support to separatists in the east of the country following Russia's annexation of Crimea.

Western officials have been concerned about possible new cyber attacks as tensions mount over the potential for a new Russian invasion of Ukraine.

The targeting of Ukrainian government websites comes at the end of a week of international diplomacy over Ukraine between Russia, the United States and NATO allies that ended without agreement and with both sides signalling worse hostilities could follow.

Russia said dialogue was continuing but was hitting a dead end as it tried to persuade the West to bar Ukraine from joining NATO and roll back decades of alliance expansion in Europe - demands that the US has called "non-starters".