RUSSIA has been forced to admit that it was struck by Ukraine with American ATACMS missiles overnight - as the UK slammed "depraved" despot Vladimir Putin.
Just days after the US approved Ukrainian use of its far-reaching rockets - Kyiv's forces used them to blitz a military depot storing ammunition and anti-aircraft missiles.
It was the first time ever that embattled Kyiv was able to unleash the ballistic rockets on Russian soil - as the world today marks 1,000 days of Putin's bloody and illegal war.
Reports surfaced on Tuesday morning about the missile strike - with a Ukrainian defence source telling RBC that they had indeed used ATACMS rockets.
The Russian defence ministry later confirmed the hit - saying missiles supplied by the US were used to target the ammo arsenal in Bryasnk.
Fragments of one of the damaged rockets landed on the "technical territory" of the military facility and sparked a fire, Russia had to begrudgingly concede.
Top brass claimed they successfully shot down five and damaged one more.
News of the strike came just hours after Vladimir Putin green-lit a new nuclear doctrine, in retaliation to Ukraine's new missile permissions.
It equated use of the Western weapons by Ukraine with an act of aggression by those allied countries supplying them with weapons.
The Kremlin said it marked the crossing of a red line - officially putting nuclear retaliation on the table.
Downing Street slammed the Russian government today for the fresh WW3 threat - with a Starmer spokesperson saying: "It would be fair to say it's the latest example of irresponsibility that we've seen from the depraved Russian government.
"We remain steadfast in our support for Ukraine and the defence of an illegal invasion, and we've always said that the defence of the UK starts in Ukraine."
How Ukraine could turn war around in WEEKS using US missiles & expose Putin as a paper tiger after 1,000 days of hell
The US on Sunday approved a decision that allowed Ukraine to fire some American ATACMS rockets inside Russia for the first time in almost three years of war.
A Ukrainian defence source told RBC: "Indeed, ATACMS was used for the first time to strike the territory of the Russian Federation.
"The strike was carried out on a facility in the Bryansk region, it was successfully destroyed."
Karachev is some 130km from the Ukrainian border.
Ukrainian outlet Censor said some 12 explosions occurred during the overnight strike.
Ukraine later confirmed that the warehouse they struck was storing North Korean ammunition and anti-aircraft missiles, via official Andriy Kovalenko on Telegram.
It follows reports that Putin's ally and fellow despot Kim Jong-Un is readying to send 100,000 troops to help him in his brutal war.
Mad Vlad was left raging when US President Joe Biden finally approved use of the far-reaching rockets by Ukraine on Sunday.
His puppet Peskov swore this morning that the use of Western non-nuclear missiles by Ukraine's armies could spark a nuclear response.
Russia has issued countless similar threats in the past - invoking fears of possible nuclear escalation in the West.
Peskov said the new policy "concerns the fact that the Russian Federation reserves the right to use nuclear weapons in the event of aggression with the use of conventional weapons against it".
When asked if the new policy means Russia views long-range missile firing as an attack by a non-nuclear state (Ukraine) with the support of a nuclear state (US) - and provokes the possibility of Russia using nukes in response - Peskov said "Yes, that is what is being discussed".
Former Russian president and Putin's right-hand man Dmitry Medvedev, speaking about the updated nuke policy, said: "The use of the Alliance missiles in this way can now be qualified as an attack by the bloc countries on Russia.
"In this case, the right arises to launch a retaliatory strike with weapons of mass destruction on Kyiv and the main NATO facilities, wherever they are.
"And this is already World War Three."
Pressed this morning on the embarrassing security failure in Bryansk, he said of the ATACMS missile: "I don’t have this information.
"But I have no doubt that our military has the situation under control."
The move to relax missile permissions followed "one of the largest" air attacks of the Ukraine war so far with 120 missiles and 90 drones fired by Russia.
It puts into play Britain's Storm Shadow and France's SCALP missiles - ramping up pressure for Ukraine's other Western allies to follow the US lead.
Andrey Gurulev, reservist Russian army general, MP and pro-Putin TV propagandist, warned of a full-scale nuclear strike on Britain.
“There are individual targets that can be hit with….demonstrative warning strikes,” he said.
“The first candidate to get a nuclear bludgeon….is the UK.”
He also declared "if anyone has the urge to launch ATACMS, SCALP, Storm Shadow missiles….there will be essentially nothing left of America trying to pull us into escalation."
As the world marks 1,00 days of war in Ukraine on Tuesday, Putin's puppet Vasily Nebenzya told the Security Council the use of Western missiles in Russia amounted to "suicidal strikes".
He urged a rethink from Britain and France.
"Perhaps Joe Biden himself, for many reasons, has nothing to lose," he said.
How Ukraine could turn war around in WEEKS using US missiles
EXCLUSIVE by Sayan Bose, Foreign News Reporter, and Georgie English, Foreign News Reporter
Today marks 1,000 days of Vlad's gruelling war in Ukraine that has left more than a million soldiers and civilians dead or wounded.
Putin's forces invaded their neighbouring nation in February 2022 as part of the deluded tyrant's plan to rebuild the Soviet Union amid his paranoid fears over Nato.
Almost three years later, Kyiv's battle-weary troops are fighting to the death on multiple fronts.
They have faced several setbacks in the grinding conflict as Russia has made slow but incremental gains over Ukrainian territory.
But the green light from the US that now allows Ukraine to use long-range ATACMS missiles could be a game changer, an expert has said.
Colonel Hamish de Bretton-Gordon told The Sun how Ukraine could turn the war around in six weeks when provided with unwavering support from key allies in the West.
The former British army officer said Washington's decision to allow Ukraine to use ATACMS - and the prospect of Britain's Storm Shadow missiles joining the war effort - is a "significant development".
He explained: "Since day one Putin and his close aides have been threatening a nuclear strike if we escalate it, and today is the 1,000th day of this conflict, and it hasn't happened.
"It should embolden our leaders, who must now realise that Putin's threats are completely hollow.
"With the Russian boxer on the ropes, now is the time that we enable the Ukrainians to absolutely put in the killer punch and be in a really good position for the expected ceasefire."
He added: "The fact that the Russians have been so vehement in their verbal attacks against the use of Nato missiles shows that this is a significant step.
"It could allow Ukraine to gain a good position in [the next] six weeks which will be important for Zelensky if Trump forces a ceasefire after getting back in office."