Europe has shown its "strongest show of force against Russia" yet as tensions skyrocket and UK government officials declare "the invasion of Ukraine has begun".
German Chancellor Olaf Scholz made his biggest move yet after killing off the Nord Stream 2 pipeline project.
"The situation has fundamentally changed," he said, in what experts believe will come as a shock to Russian president Vladimir Putin.
Meanwhile, Britain has announced it will impose sanctions on five Russian banks and three "very high-net-worth individuals" after the deployment of troops to two Moscow-backed regions of Ukraine.
Prime Minister Boris Johnson said overnight: "The UK and our allies will begin to impose the sanctions on Russia that we have already prepared using the new and unprecedented powers granted by this House to sanction Russian individuals and entities of strategic importance to the Kremlin."
Russian tanks were on the move and around 10,000 Russian troops have entered the breakaway territories of Luhansk and Donetsk in eastern Ukraine – known collectively as the Donbas region — while Russian authorities have denied Ukraine's right to sovereignty.
Videos show Russian military vehicles in two breakaway areas of eastern Ukraine — that Putin recognised as independent states on Monday - effectively annexing them into Russia.
The world is now holding its breath after footage of Terminator-style Russian forces was taken from Makiivka, in the so-called Donetsk People's Republic (DPR), and the neighbouring Luhansk People's Republic (LPR).
"We are waking up to a very dark day in Europe. It's clear from what we have already seen and found out today that Russia's President Putin has decided to attack the sovereignty of Ukraine and its territorial integrity," UK health secretary Sajid Javid told Sky News.
"You can conclude that the invasion of Ukraine has begun."
Ukraine President Volodymyr Zelenskyy addressed the nation live on television, warning Russia his country was unafraid and "will not concede anything to anyone".
The United Nations Security Council held an emergency meeting in response to the situation, with US ambassador Linda Thomas-Greenfield describing as "nonsense" Putin's reference to the troops as "peacekeepers".
"We know what they really are," Thomas-Greenfield said, saying Putin's address amounted to a "series of outrageous, false claims" that were aimed at "creating a pretext for war".
As the crisis rages on, US intelligence has this week revealed that Putin has given the order for his troops to invade Ukraine, with the Russian army now poised to strike.
Around three-quarters of Russia's total forces have reportedly been deployed against Ukraine, with almost 200,000 Russian and separatist forces positioned near the border.
Ukraine shelled 80 times in 24 hours
Ukraine's Defence Ministry has claimed Ukrainian territories were shelled a staggering 80 times in just 24 hours from the breakaway regions of Luhansk and Donetsk.
In a statement, the ministry confirmed 58 of those incidents were from weapons which are specifically banned under the Minsk agreements – a ceasefire pact hashed out in 2014 and 2015.
However, Putin has stated that the Minsk accord "no longer exists".
At least one fatality has been recorded in Ukraine so far, as well as a handful of injuries.
'Strongest show of force yet against Russia'
Chancellor Scholz said overnight that Berlin will halt the $10b Nord Stream 2 gas pipeline from Russia, singled out by allies as a chink in Europe's united front, as the West begins to fight back against Russia.
Construction of the pipeline has recently been completed, but Scholz said Germany had decided to "reassess" the certification given Russia's latest actions in east Ukraine.
In what has been described as "his strongest show of force yet against Russia" by Sky News, Scholz finally ruled in favour of the allies after Germany was reluctant to impose sanctions on the issue.
Dubbed a "significant move" by the Associated Press, the Nord Stream is a key pipeline that runs between Germany and Russia. Germany is heavily reliant on Russia for its gas with approximately half of its supply coming from there.
"That's a huge step after refusing to be drawn on it in public for months," Moscow correspondent for the Financial Times Max Seddon wrote.
"It'll have major consequences for European energy security and suggests the western sanctions against Moscow will be tough.
Biden's sanctions revealed
US President Joe Biden spoke earlier today, describing the crisis as "the beginning of a Russian invasion of Ukraine".
He also announced a slew of new sanctions against Russia.
"We're implementing full blocking sanctions on two large Russian financial institutions: VEB and their military bank," he said.
"We're implementing comprehensive sanctions on Russia's sovereign debt. That means we've cut off Russia's government from Western financing. It can no longer raise money from the West and cannot trade in its new debt on our markets or European markets either.
"We'll also impose sanctions on Russia's elites and their family members. They share in the corrupt gains of the Kremlin policies and should share in the pain as well.
"We've worked with Germany to ensure that Nord Stream 2 will not … move forward."
Biden said if Moscow "continues its aggression" there could be tougher sanctions to come."
Insane price rise over Russian crisis
Oil prices surged close to $100 per barrel in a seven-year-high as major crude producer Russia prepared to send troops into the two breakaway regions of Ukraine.
Boris Johnson says sanctions incoming
The UK's Johnson has warned Russia the "first barrage of UK economic sanctions" will be revealed.
Johnson said the Russian leader has begun a "full-scale invasion of Ukraine", but will soon find he has "gravely miscalculated".
Johnson is holding an emergency meeting overnight to discuss the UK's response and what sanctions they will place.
"If Vladimir Putin continues down this track of violence, of aggression, of a full-scale invasion, of encircling Kyiv itself, which is what he seems to be proposing to do, capturing the Ukrainian capital, it is absolutely vital that that effort, should not succeed," he said.
Ukraine President's defiant TV address
Ukraine's Zelenskyy addressed the nation this morning, warning that the country is "not afraid" and "will not concede anything to anyone".
"We are on our land. We are not afraid of anything and anyone, we don't owe anything to anyone, we will not concede anything to anyone," Zelenskyy said in the 2am address.
"It's not February 2014 but February 2022. It's a different country. There's a different army. There's a single goal: peace."
The president said he expected international powers who have been vocal about the buildup in recent weeks to respond immediately.
"It is very important to see who is our real friend and partner and who will continue to scare the Russian Federation with words," he said.
Ukraine military reports two dead
The Ukrainian military revealed two soldiers were killed and 12 were wounded in shelling by pro-Russian separatists in east Ukraine.
The military said on its Facebook page it had recorded 84 cases of shelling by separatists during the "ceasefire".
"As of 11 o'clock this morning, February 22, 13 ceasefire violation[s] by the Russian occupation forces were observed, including 10 when the Russian occupation forces utilised weapons prohibited by the Minsk Agreements," the military revealed.
"To implement the security measures aimed at protecting the civilian population, the State Emergency Service of Ukraine pyrotechnic units of the Joint Forces de-mined almost 2 hectares of land and transferred for disposal two items of explosive ordnance.
"The Joint Forces units continue to carry out assigned missions of defeating and deterring the armed aggression of the Russian Federation."
Putin's peacekeepers "nonsense"
The United Nations Security Council has held an emergency meeting in response to the crisis unfolding in Ukraine.
US Ambassador Linda Thomas-Greenfield heaped scorn on Putin's assertion that the Russian troops would take on a "peacekeeping" role.
The US envoy said an earlier speech by Putin amounted to a "series of outrageous, false claims" that were aimed at "creating a pretext for war".
During the meeting, members voiced serious concerns about the impact of the invasion, with one representative revealing a disturbing prediction.
"In our past two meetings on Ukraine, I had mentioned nearly 3 million Ukrainians will need food, shelter and lifesaving assistance, right now," the representative said.
"The UN estimates the humanitarian toll will expand significantly, should Russia further invade.
"Already Russian proxies dramatically increase shelling and artillery fire over the weekend, killing Ukrainian civilians and soldiers.
"If Russia invades Ukraine even further, we will see a devastating loss of life, unimaginable suffering [and] millions of displaced people will create a refugee crisis across Europe."
Russia's ambassador to the UN Vasily Nebenzya told the meeting that Moscow was still open to a diplomatic solution.
"Allowing a new bloodbath in the Donbas is something we do not intend to do," he added, referring to the region encompassing Donetsk and Lugansk.
Invasion 'appears to have started'
Armoured vehicles have been filmed crossing the border from Russia into Ukraine, which one expert has taken as a sign that the invasion was now under way,
Hans Kristensen, the director of the Federation of American Scientist's Nuclear Information Project, has taken to Twitter this morning to share information that the Russian invasion "appears to have started" just hours after Putin broke international law to recognise two rebel Ukrainian regions.
He also shared footage from the 301 news network, which show "columns of equipment" from the Russian Federation entering the republics of Donbas.
Troops sent to rebel regions
Moscow has ordered troops to the two rebel Ukrainian regions in a decree released almost immediately after Putin recognised the territories.
According to the New York Times, the Kremlin has since ordered Russia's defence ministry to send forces to the pro-Russian regions to carry out "peacekeeping functions" in the so-called Donetsk and Luhansk People's Republics.
It's not yet known whether troops will stay in the area controlled by the separatist republics, or progress further.
Zelenskyy said in a tweet he was "urgently preparing an address" in response to the move, and that he had been speaking with world leaders.
Morrison slams Russia's 'nonsense' peacekeeping claim
Australian Prime Minister Scott Morrison has dismissed Moscow's claim that troops were being sent to Ukraine's rebel regions for "peacekeeping" reasons.
"Some suggestion they are peacekeeping is nonsense. They have moved in on Ukrainian sovereign territory," Morrison said yesterday.
"I hope for the best in terms of diplomatic efforts that are being pursued - trying to avoid a violent confrontation with terrible human consequences. We cannot have threats of violence.
"The moment other countries put in place strong and severe sanctions on Russia, we will be in lockstep and moving just as quickly.
"Russia should step back. It should unconditionally withdraw. It's unacceptable, it's unprovoked, it's unwarranted."
Russian troops 'just 3.4km from Ukrainian border'
Alarming new footage has revealed Russian forces storming towards the Ukrainian border, with troops now just 3.4km away.
In a video shared on Twitter by Yeshiva World News reporter Moshe Schwartz, a "large column of about 45 tanks" can be seen in the Belgorod region of Russia travelling west towards Ukraine.
Schwartz has geolocated the video, and said he had "high confidence" it placed the forces within a handful of kilometres from Ukraine.
Five Ukrainian 'saboteurs' killed
Russian military officials have claimed that five Ukrainian "saboteurs" have been killed while attempting to breach the border.
According to the officials, the "diversionary reconnaissance" group were killed and their vehicles destroyed.
However, Ukraine has strenuously denied the allegations, insisting no Ukrainian forces were in the Rostov region where the alleged deaths occurred.
Foreign Minister Dmytro Kuleba denied that allegation and a slew of other claims from Russian officials, while Moscow continues to deny it was planning to invade Ukraine, despite intelligence from the West suggesting otherwise.