Andrei Fedorov, a Kremlin adviser and former deputy foreign minister, told the BBC on Tuesday that he could not rule out action against Britain. "I cannot exclude 100 percent that there might be some semi-military action against Britain," he said, as reported by Al Jazeera.

He referred to a possible "technical reaction" including a "hackers attack from unknown source", and said: "Something might happen with enterprises, with the factories which are producing drones."

Read the construction of that threat

Every element is deniable, and that appears to be deliberate.

"Semi-military" is not a category in international law or in military doctrine. "Hackers attack from unknown source" describes an act while denying attribution in the same phrase. "Something might happen with enterprises" identifies a target without naming a facility or promising anything. And the speaker is an adviser and former official, not a serving minister.

This is a threat engineered to be understood and disclaimed at once. Reporting it accurately means quoting it exactly and not converting it into a plainer statement than the one that was made. No specific UK facilities were named.

The Kremlin's stated position

Dmitry Peskov, the Kremlin spokesman, said on Monday that Britain is "participating in this war" and adding "fuel to the fire" through missile support.

That followed Prime Minister Andy Burnham's visit to Kyiv on August 24, where Britain agreed to declassify blueprints for missile components so Ukraine can produce them. Moscow treats the transfer as evidence of direct British involvement, which is the argument the warning rests on.

Burnham's response to reporters was to ask "who started the fire in the first place", a reference to the Russian invasion of February 2022.

A discrepancy worth flagging

This report gives the missile's range as approximately 240km. Our account yesterday, from a different Al Jazeera piece, gave a range of about 560km with the ability to strike 240km inside Russian territory.

Those may be describing different things, a total range against a practical reach from available launch points, or one may simply be wrong. We are recording both with their sources rather than choosing.

What we could not establish

We could not establish whether Fedorov speaks for the Russian government, whether British security services have assessed a specific threat, whether any UK site has been targeted, or how the British government has responded beyond the prime minister's remark. We verified this account from a single publication, which is itself relaying a BBC interview we have not heard.