Ukraine fired six American-supplied longer-range missiles at Russia’s Bryansk region, Moscow said on Tuesday, in what would be Kyiv’s first use of the weapons inside Russia in 1,000 days of war.

The reported use of the Army Tactical Missile System, known as ATACMS, came as Russian President Vladimir Putin formally lowered the threshold for using nuclear weapons, opening the door to a potential nuclear response by Moscow to even a conventional attack by any nation supported by a nuclear power. This could include Ukrainian attacks backed by the US.

The developments marked a worrying new escalation in the conflict that has repeatedly ratcheted up international tensions.

POLITICS Ukraine
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US officials recently expressed dismay at Russia’s deployment of North Korean troops to help it fight Ukraine, while Moscow seethed when Washington eased restrictions on the ATACMS in recent days.

The 1,000-day mark has magnified scrutiny of how the war is unfolding and how it might end, amid signs that a turning point may be coming with US President-elect Donald Trump entering the White House in about two months’ time.

Mr Trump has pledged to swiftly end the war and has criticised the amount the US has spent on supporting Ukraine.

Neither Russia nor Ukraine can sustain the war for a long time, analysts say, although Russia is able to keep going for longer due to its vaster resources.

Ukraine’s forces are under severe Russian pressure on the battlefield at places along its approximately 600-mile (1,000km) front line where its army is stretched thin. Ukrainian civilians, meanwhile, have repeatedly been hit by Russian drones and missiles.

On Tuesday, Ukraine claimed it hit a military weapons depot in Russia’s Bryansk region in the middle of the night, although it did not specify what weapons it used.

The Ukrainian general staff said that multiple explosions and detonations were heard in the targeted area, around Karachev.

In a statement carried by Russian news agencies, the Russian defence ministry said the military shot down five ATACMS missiles and damaged one more.

The fragments fell on the territory of an unspecified military facility, the ministry said. The falling debris sparked a fire, but did not cause any damage or casualties, it said.

POLITICS Ukraine
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Neither side’s claims could be independently verified.

Karachev is roughly 70 miles (115km) from the Russia-Ukraine border.

Ukraine, in the course of the war, has been able to reach much deeper into the vast country – but with drones rather than missiles.

Russian officials have, for instance, reported intercepting Ukrainian drones over Moscow, which is about 310 miles (500km) from the border and most recently Izhevsk, a city about 900 miles (1,450km) from the frontier.

Earlier on Tuesday, Ukrainian officials reported that a third Russian strike in as many days on a residential area in Ukraine had killed at least 12 people, including a child.

The strike by a Shahed drone in the northern Sumy region late on Monday hit a dormitory at an educational facility in the town of Hlukhiv and wounded 11 others, including two children, authorities said, adding that more people could be trapped under the rubble.

On Sunday, a Russian ballistic missile with cluster munitions struck a residential area of Sumy, killing 11 people and wounding 84 others.

On Monday, a Russian missile barrage sparked apartment fires in the southern port of Odesa, killing at least 10 people and wounding 43.

Ukrainian President Volodymyr Zelensky said that the series of aerial strikes proved that Mr Putin was not interested in ending the war.

“Each new attack by Russia only confirms Putin’s true intentions. He wants the war to continue. Talks about peace are not interesting to him. We must force Russia to a just peace by force,” Mr Zelensky said.