Video footage of tanks and other armoured vehicles being loaded onto railway flatcars raised hopes on Tuesday morning that Russia may be dialling down plans to invade Ukraine.
The Defence Ministry in Moscow, which put out the clips, also said some units of the Southern and Western military districts had completed their exercises, near Ukraine, and were starting to return to base.
But western sources say they have seen no sign of de-escalation in the threat of an attack on Ukraine, or withdrawal of Russian forces.
In fact, they believe the opposite is happening with Vladimir Putin continuing to build up his combat capabilities very close to the Ukrainian border, putting them in position from where they could launch a lightning invasion to seize Kiev within days.
Mr Putin said a decision on a partial withdrawal of troops had been taken.
But the tank footage could be part of forces going in or out of key areas, or being manoeuvred around, according to western sources.
They also warned it may be a play in a “false flag” operation to suggest Russia is not going to invade, only to do so in response to a fabricated attack, blamed on Ukraine’s government, possibly on areas of the country held by Moscow-backed separatists.
Fuelling such fears, Mr Putin described the situation in east Ukraine’s breakaway regions as “genocide”.
Just hours before the Defence Ministry said some troops were withdrawing, a US defence official said Russian units were actually moving closer to the Ukrainian border, not away from it.
Huge uncertainty hung over the region and what is actually happening on the ground in particular areas.
Nearly 100 Russian battalion tactical groups, though, are believed to be massed around Ukraine’s borders, amounting to about 60 per cent of Russia’s ground combat forces and about half its combat air power, according to western sources.
Commercial satellite images taken on Sunday and Monday showed a flurry of Russian military activity at several sites near Ukraine, according to the private US company that released the pictures.
Maxar Technologies highlighted the arrival of several large deployments of troops and attack helicopters as well as moving more ground attack aircraft and fighter-bomber jets to forward locations.
The planning is detailed and is understood to include measures such as setting up field hospitals near the Ukrainian border, moves which might not be happening unless the Russian President was seriously considering an invasion.
Foreign Secretary Liz Truss warned on Tuesday morning that Britain believes an invasion is “highly likely”.
Mr Putin is not believed to have yet made a decision on military action which could be very significant given the scale of the 130,000 forces mobilised.
In comments which buoyed stock markets seizing on them as a new sign of easing East-West tensions, he stressed on Tuesday afternoon that Russia is ready for talks with the US and Nato on limits for missile deployments and military transparency. This raises hopes of a possible diplomatic path to avert war.
They were sparked on Monday by Russian foreign minister Sergei Lavrov who signalled that Moscow was open to keep discussing its security grievances, particularly the possibility that Ukraine may some time in the future seek to join Nato.
However, with so many troops ready for action, Mr Putin could launch an invasion within hours, Foreign Secretary Ms Truss made clear, with suggestions it may happen as early as Wednesday.
This was dismissed by Russian Foreign Ministry spokeswoman Maria Zakharova who said: “February 15, 2022 will go down in history as the day Western war propaganda failed. Humiliated and destroyed without a single shot fired.”
However, the US, Britain and their allies are braced for immediate Russian action, which would be met with a wave of punitive sanctions and other retaliatory measures, or a protracted stand-off inflicting economic and psychological damage on Ukraine and its people.