The British Ministry of Defense published a video on Monday showing Ukrainian troops and British troops gathered around tables, with British instructors showcasing ammunitions of depleted uranium.

Ukrainian troops had just completed their training to operate tanks and other heavy armored vehicles. 

On March 21, the British government vowed to supply 14 of its 227 Challenger 2 main battle tanks to Kiev's forces along with ammunitions of depleted uranium to be used in combat. 

The MoD said in a statement that day that "any impact to personal health and the environment from the use of depleted uranium munitions is likely to be low."

Russian President Vladimir Putin warned that Russia would be "forced to react accordingly" to the use of "weapons with a nuclear component."

On Saturday, Putin vowed to retaliate by moving 'tactical' nuclear weapons into Belarus.

The ammo seen in the documentary is marked as "inert", meaning that the instructors used replicas. Next to it are displayed blue and silver-colored training shells, an expert told Declassified.

Read more: UK depleted Uranium projectiles to Ukraine a new provocation: Moscow

According to Doug Weir from the Conflict and Environment Observatory, "The orange and black munition in the video appears to be an inert display version of the UK’s 120mm 'CHARM3' DU ammunition," noting that CHARM3 is a technical term to refer to the UK's depleted uranium shells. 

"When DU munitions hit hard targets such as tanks or armored vehicles, they fragment and burn, generating chemically toxic and radioactive DU particulate [microscopic particles] that pose an inhalational risk to people," he added.

"Managing DU contamination appropriately will be a further burden for Ukraine, in a conflict that has already generated serious pollution problems."

The worrisome part of this documentary is that a US troop appeared to be present at the training session.

As per the Declassified UK report, "the presence of an American soldier at the training session could escalate tensions further", particularly because Washington denied sending any of its own DU stocks to Ukraine last week.

The MoD said in a statement on March 21 that depleted uranium "is a standard component and has nothing to do with nuclear weapons."

This statement effectively implies that the government is overlooking the disastrous impacts of the ammunitions on the health of populations, as seen in Iraq and Libya where rates of cancer cases and birth defects spiked following US and NATO invasions. 

According to a researcher from the MoD-funded RUSI think tank Jack Watling, he confirmed to the Spectator yesterday that depleted uranium was toxic.

"But when Russian troops do come into contact with one of these projectiles, the fact that the uranium will be traveling at around 1,800 metres per second and burning up as it flies will be more concerning to any target than its radioactivity," he added.

UK Defence Secretary Ben Wallace praised earlier today Ukrainian troops for having completed their training on British Challenger 2 tanks in the UK.

"They return to their homeland better equipped, but to no less danger. We will continue to stand by them and do all we can to support Ukraine for as long as it takes."

Read more: Europe may face cancer, birth defects if Kiev uses depleted uranium