Boris Johnson says Ukraine crisis has entered ‘most dangerous moment’

UK PM visits Nato’s headquarters as Russian forces continue military buildup on Ukraine border

Boris Johnson has said the Ukraine crisis has entered “the most dangerous moment” on a visit to Nato’s headquarters as Russian forces continued their military buildup on the borders of its southern neighbour.

The prime minister said “our intelligence remains grim” but told reporters in Brussels that he didn’t think a decision has yet been taken by the Russian president, Vladimir Putin, to order an invasion.

“This is probably the most dangerous moment. I would say that in the course of the next few days, in what is the biggest security crisis that Europe has faced for decades, we’ve got to get it right,” Johnson said.

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Military analysts estimate Moscow has massed more than 135,000 troops on the borders of Ukraine, both in Russia and in Belarus – and some now believe nearly all the necessary elements are in place if Putin wanted to attack.

Johnson’s concern was echoed by the Nato secretary general, Jens Stoltenberg. “This is a dangerous moment for European security. The number of Russian forces is going up. The warning time for a possible attack is going down,” he said.

Johnson said the UK and Nato would not intervene militarily if Ukraine was attacked, but repeated that Moscow would face unspecified economic sanctions. A conflict, he added, would be a disaster for both countries, as he called on Putin to de-escalate.

“I know that in the Kremlin and across Russia they must be wondering whether it is really sensible to expend the blood of Russian soldiers in a war that I think would be catastrophic,” the prime minister said. “And all I would say is that this is the moment now to think of another way forward.”

In response to a question from the BBC, Johnson did indicate the UK may be willing to provide arms to support any Ukrainian insurgency if Russia were to invade, saying: “It’s possible, I don’t want to rule this out.”

Johnson added: “We will consider what more we can conceivably offer, but I have to tell you that, you know, the Ukrainians are well prepared. There are things that we’ve offered that they, in fact, don’t seem to need because they think they have them in enough numbers already.”

Last month, Britain gave 2,000 light anti-tank weapons to Ukraine’s military, to boost the country’s defensive capability.

Ukraine’s army numbers 145,000 personnel, according to the International Institute for Strategic Studies, but there are up to 400,000 people who have fought in the conflict with Russian-backed separatists in the eastern Donbas region who Kyiv says may be willing to join an armed resistance.

The UK prime minister said he had agreed with the Nato chief “a package of support” to boost Britain’s military contribution to eastern European members of the alliance. Britain would be “doubling the presence” of troops in Estonia, Johnson said, where the UK contributes 900 troops to a Nato battlegroup it leads.

The RAF, he said, would help provide “air policing in Romania, increasing the number of Typhoons we are deploying out of Cyprus” and the UK will send a T45 destroyer and the offshore patrol ship HMS Trent to the eastern Mediterranean.

Stoltenberg said further discussions about increasing Nato’s defensive presence in eastern Europe were ongoing, including on the establishment of Nato battlegroups “in the Black Sea region, in Romania” in addition to those stationed in Estonia, Latvia, Lithuania and Poland.

The Nato chief said he had sent a letter earlier on Thursday to the Russian foreign minister, Sergei Lavrov, offering to discuss more transparency around exercises, as well as nuclear arms control. “We are prepared to listen to Russia’s concerns,” he said, adding that Nato was ready for a “serious conversation on arms control”.

Johnson heads to Poland for meetings in Warsaw with the prime minister, Mateusz Morawiecki, and the president, Andrzej Duda, as part of a wider burst of British diplomatic activity. The UK foreign secretary, Liz Truss, is already in Moscow and will be followed by the defence secretary, Ben Wallace, on Friday.

The Labour leader, Keir Starmer, is heading to Nato’s headquarters in Brussels this afternoon, where he will offer support to the military alliance in its response to the Russian threats to Ukraine. “The message is that we are firm and united in our support for Nato,” Starmer told the Times in an interview overnight.