Russia could launch a second assault on Kyiv, despite losing a quarter of its combat ability, it was feared tonight.
President Vladimir Putin could still pitch a large Belarusian army from the north after it was boosted from 45,000 troops to 85,000.
Ukrainian President Volodymyr Zelensky said Russia’s Black Sea blockade could starve millions and the battle for key Severodonestk could cost Donbas.
American think tank The Atlantic Council said Belarus military exercises: “... form part of a speculation over the possibility of a renewed cross-border offensive into northern Ukraine..”
It warned Belarus army drills which began on June 7 are aimed at escalating from “peacetime to wartime” and that “there is no denying the uptick in activity.”
The Council said: “Ukrainian officials have noted intensifying reconnaissance and the deployment of additional unit to border districts.
“Some believe this Belarusian saber-rattling is an indication that Moscow may be considering a new assault on Kyiv.”
Russia may have lost a quarter of its entire combat ability, including over 1,000 tanks destroyed, over 100 warplanes brought down and scores of helicopters blown up.
Ukraine’s troops are trying to counter attack Russian advances into key city Severodonestk, in Luhansk whilst Russia is pitching reinforcements into the decisive battle.
Supremacy in Luhansk would mark a significant victory in Russia’s invasion.
Ukrainian President Volodymyr Zelensky warned Severodonetsk is the “epicentre” of the battle for Donbas.
He said: “This is a very fierce battle, very hard, perhaps one of the most difficult of the entire war.”
A former British military intelligence officer said: “If Russia has lost 25% of its military combat capability then no force could sustain such a war.
“Yet Russia is piling so much effort into Donbas and in particular Severodonetsk that it has become crucial to the Kremlin’s war effort.
“Ukraine is holding on until it can get bigger artillery weapons into the fight.”
Former Commander of British Forces in Afghanistan Colonel Richard Kemp said: “I would be cautious about various claims of Russian losses although there is no doubt they are significant.
“Securing Donbas is very important to Russia and has become a major priority.
“And Ukraine is outmatched by Russian artillery, which is why the multi-launch rocket systems promised by the UK and US are so important to Kyiv.”