Australians in Ukraine have been warned to leave as soon as possible amid growing fears an imminent Russian invasion.
The Department of Foreign Affairs and Trade, alongside Foreign Affairs Minister Marise Payne, have urged Australian citizens and visa holders to exit Ukraine sooner rather than later.
DFAT's updated no travel advice comes after talks with allies US, UK and Canada about the escalating situation in eastern Europe which could mark the biggest security threat on the continent since the 1990s.
Foreign Affairs Minister Marise Payne said the advice was the "appropriate thing to do to protect Australians", given flights could be cancelled at short notice.
Commercial flights are still operating in and out of Ukraine.
"This is a cautious and prudent step, it is because the situation is unpredictable. And it's about protecting Australians on the ground," she told ABC's RN Breakfast.
Around 1400 Australian citizens are currently in Ukraine, with the federal government already directing the departure of family members of Australian embassy staff in the capital Kyiv.
The federal government at this stage has ruled out any military involvement, but would support NATO and allies through other means such as additional economic sanctions.
Senior analyst at Australian Strategic Policy Institute, Dr Malcolm Davis believes the situation has gone beyond diplomatic repair, warning anyone in the country should start heading west to NATO's eastern frontier.
NATO forces have begun bolstering up its collective borders with Russia. 8500 US troops are currently on standby for deployment to eastern Europe.
"While there will be attempts to find a diplomatic offramp, none of these will be taken." Dr Davis said.
"At some point in the next few weeks, possibly the next few days, the Russians will do a major invasion."
Dr Davis noted response likely to be taken by the Commonwealth will be to expel Russian diplomats, believing the government will not be able to have relations with another country which is threatening civilian lives.
"I don't see how we could have diplomatic relations with Russia, if they're inflicting massive loss of civilian lives in Ukraine," he said.
ANU Russia expert Dr John Besemeres said Ukrainians would push back against Russian occupation.
"There are an awful lot of weapons in Ukraine, and an awful lot of people who've had training with those weapons," Dr Besemeres said.
"There's every possibility that they could take a large part of the Ukraine and set it up as their own. But Ukrainians will fight back and it will be a dirty war."
Russia has assembled close to 120,000 troops along the Belarus' and its border with Ukraine.
Dr Davis said NATO would be concerned about a possible invasion into the Baltic states; Estonia, Lithuania and Latvia.
All three countries are NATO members and an invasion by Russia would spark article five of the treaty, where an attack on one member is an attack on all members.