Britain believes that nearly half of Russian forces that have massed near Ukraine are now within 30 miles of the border, in contrast to statements from Moscow that its forces were being sent back to barracks.
Reinforcements from 14 battalions were in the process of arriving, officials added, while highlighting a pontoon bridge that had been briefly set up in Belarus in the past few days as an example of unusual military activity.
There was evidence, a defence source said, “of Russian forces leaving the deployment sites for staging areas closer to the border”. A couple of hours later, the US president, Joe Biden, warned that an attack could take place “in the next several days”.
Russia has repeatedly said it has no intention of invading Ukraine and on Tuesday announced a drawdown of troops from Crimea, accompanied by videos of tanks being loaded on to transport trains.
But the UK – in conjunction with the US – stepped up its warnings on Thursday. The pontoon bridge, revealed in satellite imagery, was built five miles from Ukraine’s borders across the Pripyat river in the Chernobyl reactor exclusion zone as part of ongoing joint exercises in Belarus between Russia and its neighbour.
Ukraine is crisscrossed with rivers, which has been highlighted as a possible hindrance to any potential Russian ground invasion unless they used pontoon bridges.
Images from Wednesday, highlighted by the defence analyst group Jane’s, showed that the bridge had been taken down. But officials said of its construction: “This activity is highly unusual and inconsistent with any past exercise.”
As part of the growing public relations efforts, the UK’s Ministry of Defence also released a short video saying that it had seen “no evidence that Russian forces are withdrawing from Ukrainian border regions”, with a map showing a possible invasion on multiple axes.
The video warned: “Defence intelligence assesses that he [Russia’s president, Vladimir Putin] would be willing to sustain thousands of casualties to get what he wants.”
However, analysts from the International Institute for Strategic Studies questioned this week whether Russia had the capacity to carry out such a wide-ranging invasion as the video suggested. John Chipman, the chief executive of the thinktank, said on Wednesday that should Russia decide to attack, “there’s probably enough combat mass now present to conduct a more limited ground operation, perhaps to seize Ukraine eastern regions”.
A key moment could come on Friday. The president of Belarus, Alexander Lukashenko, said he would meet Putin that day to decide whether Moscow’s forces would remain in Belarus after 20 February, when the joint exercises were due to conclude. Previously, both countries had said Russian forces would depart on that date.
Over the past 24 hours, independent experts have become increasingly sceptical that Russian forces are moving significantly away from the border areas, although it can take time for open-source satellite imagery or other video to emerge.
Thomas Bullock, a senior open-source analyst from Jane’s, said that it “looks like the equipment is actually being moved to positions closer to the border … there’s nothing to really indicate otherwise”.
The videos released by Russia’s Ministry of Defence, Bullock said, were heavily edited and sometimes appeared to combine clips of tanks both arriving to and leaving the rail station, making it unclear whether the armour had really been withdrawn.
“It’s a bit misleading really,” he added. “If you wanted a consistent narrative you’d just show the tanks driving to the train station. Instead, they show them going there, they come back, they’re going again. It seems a bit all over the place.”
Footage published by the Russian government had shown elements of the 136th Motorised Rifle Brigade and 42nd Motorised Rifle Division of the 58th Army, both deployed to Crimea, boarding railcars that the Russian defence ministry indicated were bound for their permanent bases in mainland Russia.
Western defence sources said they would be sceptical unless they saw evidence of forces, some of whom have deployed across Russia, returning to their bases with heavy equipment. After a smaller buildup last spring, thousands of troops remained near Ukraine, rather than going home.
The Russian newspaper Izvestia, which has good sources in the defence ministry, also reported that the 3rd and 150th Motorized Rifle Divisions were returning to their garrisons as part of the drawdown. But, as analysts noted, their permanent bases are located in Valyuki, a base just over 9 miles from Ukraine, and in Rostov region just 25 miles from the border.
“Best guess is we will see a deployment shell game,” wrote Michael Kofman, a research programme director in the Russia studies programme at the US research centre CNA. “Units redeploying around Ukraine without altering the overall picture. Some BTGs [battalion tactical groups] leaving Crimea, but even more still arriving elsewhere.”
More powerful Russian units such as the 1st Guards Tank Army had been identified moving to positions as close as 19 miles from the border this week, Bullock said, “tearing up streets” in small villages as they drove to positions within striking distance of the border.
