Russia has amassed more than 100,000 troops, along with tanks and other heavy weapons, on its border with Ukraine in recent weeks, raising fears that Europe is on the brink of its first war in decades.
The menacing display has raised fears in the West that Moscow is trying to reverse one of the outcomes of the Cold War, when Ukraine broke away from its political sphere and became an independent state.
Russian President Vladimir Putin has often called the collapse of the former Soviet Union the greatest geopolitical catastrophe of the 20and century.
After the breakdown of a series of diplomatic talks last week between Russia, the United States, the EU and the North Atlantic Treaty Organization (NATO), tensions have escalated further.
The White House has said Russia could attack Ukraine “at any time”, while NATO Secretary General Jens Stoltenberg said this week that “there is a real risk of further conflict armed in Europe”.
In Brussels, the mood is also turbulent, with a senior EU diplomat telling the BBC that “Europe is now closer to war than it has been since the outbreak of the former Yugoslavia”.
Ukrainian President Volodymyr Zelensky released a video address to the nation on Wednesday, urging Ukrainian citizens not to panic for fear of a possible invasion.
However, he said, the country had been living with the Russian threat for many years and should always be ready for war.
Polish Foreign Minister Zbigniew Rau said the risk of war in Europe was greater than at any time in the past 30 years.
The UK responded by delivering a batch of anti-tank weapons to Ukraine this week, while Sweden and Denmark have both stepped up their presence near the region.
Russia has denied planning a new military offensive, but has made several demands, with the warning that it will take unspecified “military-technical measures” if blocked.
Moscow said it began its military buildup along the Ukrainian border because it could no longer “tolerate” NATO’s eastward expansion and “gradual invasion” of Ukraine.
He asked NATO to commit to a binding promise never to admit Kiev to the alliance, and wants a formal assurance from the West to end military cooperation with Ukraine.
So far, these requests have been met with a firm “no”.
So how close is the situation to war?
Analysts say all-out war is unlikely
Paul Dibb, emeritus professor of strategic studies at the Australian National University, said the situation had become dangerous, but he did not believe there was a threat of major military action.
Analysts suggest a more likely scenario is of a limited Russian invasion along separatist-held territories in eastern Ukraine it seized in 2014.
Mr Putin could also launch a limited foray into southeastern Ukraine to join the country’s industrial heartland, the Donbass, with Russian-occupied Crimea.
“As we speak, there is evidence that new Russian troops are being brought in from the Russian Far East around Vladivostok in the region just north of Ukraine,” Prof Dibb said.
“My point of view is [that], if Putin intended to have a military attack, even a partial one, we would see these troops reinforce further in the coming days and weeks.”
This week, Russia has further strengthened its presence near Ukraine with the arrival of troops in Belarus for military exercises planned between the two countries next month.
Belarus is an ally of Russia and having troops on its territory would allow Moscow to invade Ukraine from the north.
Cyberattacks rather than an invasion?
Professor Dibb, a former deputy secretary at the Ministry of Defence, said the most likely initial scenario is that Russia will mount more crippling cyberattacks.
Just last week, Ukraine was hit by a cyberattack that defaced its government websites.
The Ukrainian government blamed Russia.
“My personal view is that it could well start, as it did in Crimea, with a cyberattack…And let’s recognize that the Russians are very good at cyber, one of the best in the world,” he said. said Professor Dibb.
Cyberattacks could potentially cut electricity and energy supplies in the depths of winter and allow Russia to spread disinformation and propaganda to Ukraine’s 8.3 million Russian residents in part of insurgency operations, he said.
Alexey Muraviev, a national security and strategy expert at Curtin University, also said Russia’s priority was not the occupation of Ukraine, but rather that its agreements be honored to prevent the expansion of NATO further east.
“For Russia, occupying Ukraine is not the number one or number two priority…the Russians are more interested in reaching a consensus with Washington and Brussels,” he told the ABC. .
West calls for sanctions against strikes
With Ukraine outside NATO and lacking alliance security guarantees, the United States and its European allies have made it clear that they are unlikely to intervene directly militarily if Russia strikes. .
Instead, some sent military aid to Ukraine and raised the prospect of new sanctions against Russia, perhaps the toughest yet, in the event of an attack.
German Foreign Minister Annalena Baerbock – whose talks with her Russian counterpart, Sergei Lavrov, also ended without a breakthrough last week – said Moscow would pay the price if it moved on Ukraine, but that the diplomacy was “the only way”.
“Each new act of aggression will have a high price for Russia, economically, strategically, politically,” she said.
US President Joe Biden predicts that Russia will “intervene” in Ukraine.
He said Moscow would pay dearly for a full-scale invasion, with its businesses possibly losing access to the US dollar, but suggested there might be a lower cost for a “minor incursion”.
The Biden administration has prepared a wide range of sanctions and other economic penalties to be imposed on Russia in the event of an invasion.
However, Mr Biden said NATO allies are not united on how to respond, depending on exactly what Mr Putin is doing, saying “there are differences” between them and that he was trying to make sure “everyone is on the same page”.
He added that a third summit with Mr Putin was “still a possibility” after the two leaders met twice last year.
China looms in the shadows
Professor Dibb does not believe new sanctions will have “any” impact in deterring Mr Putin from acting against his neighbour.
“Russians are tough people. Their history tells us that they used to absorb tough measures,” he said.
Russia has been under restrictions since its annexation of Crimea, a conflict that has claimed more than 14,000 lives in nearly eight years of fighting between Russian-backed rebels and Ukrainian forces in Donbass.
More punitive measures were added after a former Russian spy was poisoned in Britain in 2018 and following an investigation into alleged Russian interference in the 2016 US presidential election won by Donald Trump.
Professor Dibb warned that Mr Putin knows that America and European countries are unwilling to confront him with war, and that China will be watching closely.
“China and Russia are increasingly showing signs of being very, very close strategic partners, and not just politically and economically, but militarily,” he said.
“If Russia uses military force and gets away with it, then China might have more incentive to continue its military threats to unify Taiwan.”