American officials will not be drawn publicly on their intelligence assessments, but their language has hardened.

The degree of certainty with which they are now characterising Russia’s intensions towards Ukraine suggests that something has changed over the past 24 to 48 hours.

There have been a curious range and number of meetings too about which little has been revealed.

The US president had a briefing with his national security team on Thursday evening. America’s top general spoke on the phone to his Russian counterpart.

Britain’s military chief, alongside the UK defence secretary, held face-to-face talks with their Russian counterparts.

Then there was the president’s language in a primetime interview on Thursday night. “Things could go crazy quickly…” Joe Biden told NBC News as he urged American citizens to leave Ukraine now.

Was this just characteristically loose language by the president? Or did it reflect a change in the US assessment of Vladimir Putin’s intensions?

Read more: US warns invasion could be ‘any day now’

Late on Friday, a senior defence official at the Pentagon in Washington said that additional US troops will be sent to eastern Europe.

“At the direction of the president, Secretary Austin today ordered to Poland the remaining 3,000 soldiers of the 82nd Airborne Infantry Brigade Combat Team based at Fort Bragg, N.C. They are expected to be in place by early next week,” the official said.

Read more: What are NATO spy planes doing to keep tabs on the Russians?

For a few weeks now there’s been a suggestion that President Putin would not want to upstage China by mounting an invasion during the Winter Olympics.

The logic being that Putin wouldn’t want to steal Xi Jinping’s big moment. “Don’t bet on it” is now the American judgement of that assessment.

Vladimir Putin is testing Western unity and resolve which, despite protestations, seems somewhat shaky.

China’s Xi Jinping only has one eye on his Winter Games. In an emerging world order, his dominant eye is on Ukraine.

Western resolve today will shape Xi’s judgements tomorrow.