A Kremlin adviser has suggested that UK factories producing drones for Ukraine could come under attack from “unknown sources” after Britain agreed to share long-range missile blueprints with the war-torn country.

Former deputy foreign minister for Russia Andrei Fedorov said he could not “100% exclude” the prospect of “semi-military” action against Britain as Andy Burnham made a visit to Kyiv.

During the trip, which was the Prime Minister’s first overseas since entering No 10, the UK reiterated its “unwavering” support for Ukraine, which in turn handed over what officials have called a “goldmine” of battlefield data to help bolster British security.

Mr Fedorov said that “sooner or later, there might be not only verbal but maybe some visible reaction from Russia towards the UK”.

Asked to elaborate on what this might look like, he said: “There are different discussions how it should look like – it might be so-called technical reaction, maybe some hackers attack from unknown source, not from official level of course.

“There might be different political steps and I cannot exclude 100% that there might be some semi-military, for example.”

Pressed to define “semi-military” he told BBC Newsnight: “For example, something might happen with enterprises, with the factories which are producing drones for Ukraine, etc etc.”

Asked whether this meant British factories in Britain being attacked militarily by Russia, the adviser said: “They could be attacked, not by Russia, but by… from unknown sources.”

Missile blueprint deal

During the visit, Burnham and Ukrainian President Volodymyr Zelensky signed an agreement to give the Ministry of Defence access to Ukraine's “Avengers” AI database. The AI data could lead to a “goldmine” and “revolutionise all parts of public life”, according to officials.

The first trial of the new collaboration is expected to see AI sensors protect military bases, and a second project will see the UK and Ukraine work on low-power AI chips.

Additionally, the UK agreed to declassify blueprints for British-made components for the Scalp missile, a French-produced version of the Storm Shadow that has already been used to hit targets in Russia.

Russia's presidential spokesman Dmitry Peskov said the agreement would add “fuel to the fire” of the conflict. Burnham responded: “Who started the fire? That's the question, isn't it?”

Calls for more interceptor missiles

The UK urged allies to send more interceptor missiles to Ukraine, with Burnham co-chairing his first coalition of the willing meeting. Zelensky has pleaded for more US-made Patriot interceptor missiles as stocks have diminished. Supplies of Patriots have been diverted to the Middle East since the outbreak of war with Iran, with Ukraine receiving significantly fewer missiles this year than in previous years.

Russia escalated ballistic missile strikes, killing at least 23 and wounding more than 100 in the past three days. Zelensky said the total funding gap is “27 billion” and mentioned bringing forward part of the European loan or unlocking frozen Russian assets as options to address the funding gap.

Burnham pledges continuity

Burnham pledged “continuity” in UK approach, saying “we're not a fair-weather friend, we're here for the long haul”. He also said: “Obviously, with a change of prime minister, presumably people might think is there a change of policy – well, I'm here to say there isn't.”