UK investigating claims, but Ukrainian security service says it has ‘nothing to do with’ memos obtained by Times

China launched cyber-attacks on Ukrainian military and nuclear targets shortly before the Russian invasion, according to a report.

The UK government confirmed that the National Cyber Security Centre was investigating the allegations, which claim that more than 600 websites, including Ukraine’s defence ministry, were subjected to thousands of hacking attempts coordinated by the Chinese government.

A UK government spokesperson said: “The National Cyber Security Centre is investigating these allegations with our international partners.”

The claims are based on intelligence memos obtained by the Times. However, the Ukrainian security service denied on Friday night that it had supplied any information on the alleged attacks.

It added: “The SBU has nothing to do with the findings of the Times. The Security Service of Ukraine does not currently have such data and no investigation is underway.”

Jamie MacColl, a research fellow at the Royal United Services Institute for Defence and Security Studies, said the reported attempts appeared to fit a Chinese tactic of scanning for vulnerabilities in IT infrastructure, such as firewalls and virtual private networks.

“This sounds relatively routine to me, if true. Some Chinese groups have been retasked to collect intelligence on the Ukraine conflict. Security agencies collect information to inform policy. And that is what appears to have happened in this case.”

The Times said a series of intelligence memos, thought to be prepared by another country, detailed the scale of the hacking and included nuclear targets, which allegedly peaked on 23 February, the day before the Russian invasion.

On 18 March the US president, Joe Biden, warned his Chinese counterpart, Xi Jinping, of “consequences” if China provided material support to Russia during the invasion.

Xi and Vladimir Putin met in Beijing at the start of the Winter Olympics in February and issued a joint statement saying the bonds between the two countries had “no limits”. Xi and Putin also made clear in the statement that they opposed any further expansion of Nato.

Ciaran Martin, a professor of practice at the Blavatnik school of government at Oxford University and former head of the NCSC, said: “We should be very cautious about this in two areas. First, there is an important difference between digital spying and disruptive attack and on the basis of the information publicly available, this looks like the former.

“Second, there isn’t anything in the publicly available evidence that implies collusion between China and Russia. Added to this now, of course, is the official denial from the Ukrainian Security Service. More facts are needed but for now we should not jump to conclusions”.