Images have stoked fear Russia is about to make a move and invade Ukraine as the US has warned of “severe consequences”.
Satellite photos taken by US-based Maxar Technologies showed troops and ground forces equipment deployed in Klimovo, 13km north of Ukraine.
Equipment was also spied by satellite at Klintsy, which is 30km east of Russia’s border with the Ukraine along with at Yelnya and Pogonovo training area, which are each more than 100km away from the border.
US President Joe Biden said he believes Russian counterpart Vladimir Putin will “move in”.
"Russia will be held accountable if it invades – and it depends on what it does. It's one thing if it's a minor incursion and we end up having to fight about what to do and what to not do, et cetera," Mr Biden said.
"But if they actually do what they're capable of doing ... it is going to be a disaster for Russia if they further invade Ukraine."
Russian officials have repeatedly denied planning to invade, but the Kremlin has massed some 100,000 troops near Ukraine's borders, a buildup the West says is preparation for a war to prevent Ukraine from ever joining the NATO Western security alliance.
White House press secretary Jen Psaki also warned if the Russians did move “it will be met with a swift, severe, and united response from the United States and our allies”.
What Ukraine could mean for Australia
John Blaxland, a professor of International Security and Intelligence Studies at ANU’s Coral Bell School of Asia Pacific Affairs, said if Russia does move to take Ukraine it could come at an enormous cost for the Russian government.
“Russia is already vulnerable to sanctions after moving into the Donbas in 2014,” Professor Blaxland said.
“It would potentially lead to a significant ratcheting of pre-existing sanctions in part or in whole.”
Professor Blaxland said Australian troops would unlikely be deployed in Ukraine if there was military intervention from Russian forces.
He said former Prime Minister Tony Abbott in 2014 sought advice in potentially sending the military but was advised not to – a belief which would “unquestionably” still be held by the Morrison government.
“Abbott was advised that our forces would be extremely vulnerable against the Russian military,” Professor Blaxland said.
“He was told we don’t have the army to fight a land war in Eurasia. Also, if the Germans and Canadians aren’t prepared to do it then we won’t either.”
Mr Abbott had promised in 2014 to "shirtfront" Mr Putin after MH17 was shot down over eastern Ukraine. The Russian government denied any involvement.
Professor Blaxland said he remains optimistic the situation will not escalate as economic sanctions would greatly damage Russia. It would also be difficult and at a great cost for Russia to potentially govern Ukraine too.
He added that many countries, such as Canada for example, have offered the Ukrainians training and equipment rather than actual soldiers on the ground for potential combat.
However, he did say there were concerns if the Russians moved in on Ukraine aggressively it could open the door for China to make its move on Taiwan.
“This is the bleakest scenario,” Professor Blaxland said, adding his “greatest fear” is three nuclear-powered states in the US, Russia and China all confronting each other.
But with war in one part of Eurasia it “provides an excuse” for war in another area for example – China or Russia finding a window or excuse to invade Taiwan or Ukraine, he said.
This is also because strategically it means a major power such as the US would be preoccupied with one conflict and would struggle to engage in combat with both China and Russia at the same time.
“A lot of things could go wrong but I hope restraint will be exercised,” he said.
“Otherwise we could see the ‘MAD concept’ also known as mutually assured destruction.
“It would be a pyrrhic victory at best though with bankruptcy on all sides regardless of who wins.”
Mr Biden said a summit with Mr Putin "is still a possibility" after the two leaders met twice last year. He said he was concerned that a Ukraine conflict could have broader implications and "could get out of hand".
The US President and his team have prepared a broad set of sanctions and other economic penalties to impose on Russia in the event of an invasion and Mr Biden said Russian companies could lose the ability to use the US dollar.
Pressed on what he meant by a "minor incursion", Biden said NATO allies are not united on how to respond depending on what exactly Mr Putin does, saying "there are differences" among them and that he was trying to make sure that "everybody's on the same page".
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