Russian battleplans have called for an "overwhelming intensity of fire" on Ukraine that could kill "tens of thousands" within the opening days of a conflict, as President Vladimir Putin moved his troops within three miles of the two countries' border, the US has warned.
Tanks, trucks and artillery have been spotted just two and a half miles from Ukrainian territory in Russia's Belgorod region as new satellite images reveal convoys and troops hiding in civilian areas and the tree-lines of forests in Soloti and Valuyki - a short distance from Ukraine's Kharkiv region where major military bases are located, the Daily Mail reported.
Diplomacy is continuing despite the threat, though the Kremlin on Monday downplayed the possibility of a meeting between US President Joe Biden and Putin after the White House said that the American leader had agreed "in principle" to talks brokered by France, provided war did not break out in the meantime.
"It's premature to talk about any specific plans for organising any kind of summits," Kremlin spokesman Dmitry Peskov said, adding that no "concrete plans" had been put in place for a meeting, the Daily Mail reported.
The next high-level negotiations between the two sides are due for Wednesday this week, when US Secretary of State Antony Blinken and Russian Foreign Minister Sergei Lavrov will meet with the issue of Biden-Putin talks expected to be on the agenda.
Meanwhile Russian military exercises in Belarus which were due to end on Sunday were extended to an unspecified date, meaning 30,000 men plus ballistic missile launchers, artillery and tanks will remain in place on Ukraine's northern border and within easy striking distance of Kiev.
Biden warned at the weekend that Putin has already given the order to attack, leaving the world guessing as to where and how hard the hammer will fall.
American officials who claimed to have seen some of the Kremlin's battle plans warned that a full scale bombardment of the country is being prepared.
"We were told to expect tens of thousands of casualties in the opening days," one of the officials told The New York Times.