Vladimir Putin has warned letting Ukraine hit Russia with British missiles would amount to "war" amid a growing list of threats from the Kremlin.
Volodymyr Zelensky has been pushing on the UK and US to let his troops use their long-range missiles - the British Storm Shadow and the American ATACMS - to hit targets in Russia, and despite rumours swelling that the two old allies might grant him the privilege, there has been no breakthrough as of Thursday night.
Despite a lack of official sign-off from the West, Putin and the Kremlin think the Nato stalwarts will green-light the missiles' use - and has issued some of his gravest threats yet in response.
The 71-year-old Russian premier said sanctioning the use of Storm Shadows and ATACMS would amount to Nato countries directly entering the war in Ukraine - because programming the missiles' flight paths would have to be done by Nato personnel.
Putin has issued some of his gravest threats yet in response to rumours of the missiles' green-lighting
REUTERS
Putin told Russian state television: "So this is not a question of allowing the Ukrainian regime to strike Russia with these weapons or not.
"It is a question of deciding whether or not Nato countries are directly involved in a military conflict.
"If this decision is taken, it will mean nothing less than the direct involvement of Nato countries, the US and European countries in the war in Ukraine.
"This will be their direct participation, and this, of course, will significantly change the very essence - the very nature - of the conflict."
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Britain has remained coy on letting Ukraine hit Russia with Storm Shadows
MBDA
Putin's comments echoed those made by Kremlin spokesman Dmitry Peskov on Wednesday that Russia would hand the West an "appropriate" response if it green-lit the missile deployments.
He said: "The involvement of the United States of America and European countries in the conflict over Ukraine is direct, and each new step increases the degree of this involvement."
While Russian officials haven't yet detailed what that response would look like, State Duma chairman Vyacheslav Volodin said Moscow would be forced to use "more powerful and destructive weapons" against Ukraine.
Nato's top dogs have remained similarly coy - despite Ukraine's pleas.
On Tuesday, Joe Biden said his administration was "working that out now" when asked if he would lift restrictions on Kyiv's use of missiles like ATACMS.
Nato's top dogs have remained similarly coy despite Ukraine's pleas
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David Lammy and Antony Blinken travelled to Kyiv to meet Volodymyr Zelensky
REUTERS
Then on Wednesday, British Foreign Secretary David Lammy - who was in Kyiv with American counterpart Antony Blinken to meet Zelensky and other top Ukrainian officials - said the UK was "listening carefully", but offered precious little detail on missile deployments.
He said: "We are listening carefully and, of course, we are having discussions on a range of issues, including the military equipment that Ukraine needs to win."
While Blinken added: "Among other things, we discussed long-range fires, but a number of other things as well. And as I said at the outset, I'm going to take that discussion back to Washington to brief the President on what I heard."
But Putin has been hawkish in the past - and has previously discussed arming the West's enemies with Russian weapons to strike Western targets abroad, or deploying conventional missiles within striking distance of the US and its European allies.
