Russian troops launched their anticipated attack on Ukraine in the early hours of Thursday leading to the deaths of "around 40 people" so far, as President Vladimir Putin was condemned for breaking international law and "bringing war back to Europe".
In his address during which he called the moves a “military operation” to “protect civilians”, Putin warned other countries that any attempt to interfere or help Ukraine would lead to “consequences you have never seen”.
Explosions were heard before dawn in the capital Kyiv, and the cities of Kharkiv and Odesa as world leaders decried the start of an invasion that could cause massive casualties, topple Ukraine’s democratically elected government and threaten the post-Cold War balance on the continent.
According to an adviser to Ukrainian President Volodymyr Zelenskyy at least 40 people have died and dozens more are injured.
Mr Zelenskyy declared martial law, saying Russia has targeted the country’s military infrastructure. When military bodies and armed forces are granted authority over an area, usually invoked in times of war, natural disaster, or rebellion.
Across the globe, financial markets plunged and oil prices soared, and governments from the US to Asia and Europe readied new sanctions after weeks of failed efforts for a diplomatic solution.
Here’s how the world reacted to what Ukraine’s Foreign Minister called a “full-scale invasion”.
Prime Minister Boris Johnson said the UK will eventually use military action to stop Russia further invading Ukraine if all other options fail, as he described the events as a "catastrophe" for Europe.
In an address to the nation, he said: "Our mission is clear diplomatically, politically, eventually military, this hideous and barbaric venture of Vladimir Putin must end in failure."
Mr Johnson said Russian President Putin has “chosen a path of bloodshed and destruction” with his attack on Ukraine and that the UK and its allies would respond “decisively”.
Watch Boris Johnson's address to the nation in full:
The PM's speech comes after he chaired an emergency morning Cobra meeting to address the crisis - it will be followed by a statement in Parliament around 5pm.
Mr Johnson has called an "urgent meeting" of all Nato leaders and that he will also speak to leaders of G7 countries Canada, France, Germany, Italy, Japan, and the United States.
In a statement on Twitter, Mr Johnson said he had spoken with Ukrainian President Volodymyr Zelensky to discuss “next steps”.
A Downing Street spokesperson said Mr Johnson had assured Mr Zelensky the West “would not stand by as President Putin waged his campaign against the Ukrainian people”.
“The Prime Minister said he hoped Ukraine could resist and that Ukraine and its people were in the thoughts of everyone in the United Kingdom during this dark time,” the spokesperson said.
All UK airlines have been instructed to avoid Ukrainian airspace after the Department for Transport announced a ban on flights between the UK and Ukraine.
Defence Secretary Ben Wallace described Russia’s actions as “naked aggression against a democratic country” and said no one had been fooled by the Kremlin’s “false flags and fake narratives”.
“The Russian Federation has today further violated Ukrainian Sovereignty,” he said.
Scottish First Minister Nicola Sturgeon said the Kremlin “must face the severest consequences” for “unprovoked aggression” in Ukraine.
She tweeted: “Overnight developments in Ukraine – however anticipated – are appalling and horrific."
Britain’s ambassador to Ukraine urged UK nationals to leave Ukraine immediately.
Melinda Simmons wrote on Twitter: “We advise GB nationals to leave Ukraine immediately if you judge that it is safe to do so from your location. Please call +380 44 490 3660 if you need assistance.”
US President Joe Biden called Russia’s decision to commence a military operation an “unprovoked and unjustified attack” as he pledged new economic sanctions.
The president said he planned to address Americans on Thursday after a meeting of the Group of Seven leaders.
He said in a statement: “The prayers of the entire world are with the people of Ukraine tonight as they suffer an unprovoked and unjustified attack by Russian military forces.
“President Putin has chosen a premeditated war that will bring a catastrophic loss of life and human suffering. Russia alone is responsible for the death and destruction this attack will bring, and the United States and its Allies and partners will respond in a united and decisive way. The world will hold Russia accountable.”
Mr Biden later said his Ukrainian counterpart Volodymyr Zelenskyy had “reached out” to him following the attack by Russian forces and asked for world leaders to “speak out clearly” against Vladimir Putin’s actions.
“I briefed him on the steps we are taking to rally international condemnation, including tonight at the UN Security Council,” Mr Biden wrote on Twitter.
“He asked me to call on the leaders of the world to speak out clearly against President Putin’s flagrant aggression, and to stand with the people of Ukraine.”
He added: “Tomorrow, I will be meeting with the Leaders of the G7, and the United States and our allies and partners will be imposing severe sanctions on Russia.”
United Nations Secretary-General Antonio Guterres says Russia's attack on Ukraine — as he appealed for President Vladimir Putin to stop his troops — was “the saddest moment” of his five-year tenure.
The UN chief opened the emergency Security Council meeting late on Wednesday by urgently appealing to Putin: “In the name of humanity, bring your troops back to Russia."
"This is the saddest moment in my tenure as secretary general of the United Nations"
But during that meeting, Putin announced in the early hours of Thursday he was launching a “special military operation” in eastern Ukraine, and explosions could be heard across Ukraine.
Mr Guterres later urged the Russian president to withdraw his troops and added: “In the name of humanity do not allow to start in Europe what could be the worst war since the beginning of the century, with consequences not only devastating for Ukraine, not only tragic for the Russian Federation, but with an impact we cannot even foresee in relation to the consequences for the global economy.”
“What is clear for me is that this war doesn’t make any sense,” Guterres said, stressing that it violates the UN Charter and will cause a level of suffering if it doesn’t stop that Europe hasn’t known since at least the 1990s Balkans crisis.
NATO's chief said the “brutal act of war” has shattered peace on the European continent, as the US-led alliance mobilised more troops to move toward eastern Europe.
The alliance announced it would be beefing up its "air, land and sea forces on its eastern flank near Ukraine and Russia".
Secretary-General Jens Stoltenberg told reporters in Brussels: “This is a deliberate, cold-blooded and long-planned invasion... Russia is using force to try to rewrite history."
He said the Kremlin's actions were a “grave breach of international law” and that allies would meet to address the “renewed aggression”.
“I strongly condemn #Russia’s reckless attack on #Ukraine, which puts at risk countless civilian lives,” he wrote on Twitter.
“This is a grave breach of international law & a serious threat to Euro-Atlantic security.
“#NATO Allies will meet to address Russia’s renewed aggression.”
EU The European Union is preparing to impose the “strongest, the harshest package” of sanctions against Russia it has "ever implemented," said EU foreign policy chief Josep Borrell.
He described the Kremlin's attack on Ukraine as among "the darkest hour for Europe since the end of World War II," for which Russia will face the consequences of "unprecedented isolation".
The 27 EU leaders will be asked to approve a second round of "massive and targeted sanctions" later on Thursday at a summit meeting and they could be imposed soon after.
Mr Borrell warned the major nuclear power is threatening reprisals of any other state that comes to Ukraine's rescue - but that the EU and trans-Atlantic partners "will stand united" and their strength "should not be underestimated".
"The darkest hour for Europe since the end of World War Two" - EU foreign policy chief Josep Borrell
"This is not only the greatest violation of international law - it's a violation of the basic principles of human co-existence. It's costing many lives, with unknown consequences ahead of us," he told a press conference in Brussels on Thursday.
"The European union will respond in the strongest possible terms."
The bloc had already issued sanctions on Russia for its recognition of breakaway republics in Ukraine earlier this week and the next package will be "designed to take a heavy toll on the Kremlin’s interests and their ability to finance war," said Commission President Ursula von der Leyen as she "strongly condemned" the "unjustified attack".
“With this package, we will target strategic sectors of the Russian economy by blocking their access to technologies and markets that are key for Russia," she told a press conference in Brussels.
“We will weaken Russia’s economic base and its capacity to modernise. In addition, we will freeze Russian assets in the European Union and stop the access of Russian banks to European financial markets.”
"Innocent women, men and children are dying... President Putin is bringing war back to Europe" - Commission President Ursula von der Leyen
Similar to the first package of sanctions, she said the EU's actions will be "closely aligned" with those of allies such as the UK, the US, Canada, Japan and Australia.
She continued: "President Putin is trying to turn the clock back to the times of the Russian empire, but by doing so he is putting at risk the future of the Russian people.
"I call on Russia to immediately stop the violence and withdraw its troops from Ukraine's territory."
“In these dark hours, our thoughts are with Ukraine and the innocent women, men and children as they face this unprovoked attack and fear for their lives," said Ms von der Leyen.
“We will hold the Kremlin accountable.”
The president of the European Council, Charles Michel, has called for a meeting of the council on Thursday evening as he urged Mr Putin to “stop this war immediately”.
Mr Michel said he had spoken with Ukrainian president Volodymyr Zelenskyy as the Belgian condemned Russian’s “unjustified large scale military aggression” as well as expressing his solidarity with Ukraine.
“Today both the European Council and G7 leaders will meet to agree on further steps against Russia’s illegal acts and in support of Ukraine,” he tweeted.
The African Union's chair urged an immediate ceasefire in Ukraine “to preserve the world from the consequences of planetary conflict”. The statement by Senegal President Macky Sall and AU Commission chair Moussa Faki Mahamat also calls on Russia to respect Ukraine’s territorial integrity and international law, expressing “extreme concern at the very serious and dangerous situation”. Few among Africa’s 54 countries have publicly reacted to the invasion.
German Chancellor Olaf Scholz sharply condemned Russia’s attack on Ukraine calling it “a terrible day for Ukraine and a dark day for Europe.”
The chancellor said on Thursday morning “the Russian attack on Ukraine is a blatant violation of international law. It cannot be justified by anything.”
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He added that “Germany condemns this reckless act by President Putin in the strongest possible terms.”
Scholz said in a written statement that “our solidarity is with Ukraine and its people. Russia must stop this military action immediately."
He added Germany would coordinate closely with others within the framework of the G7, NATO and the European Union.
“We woke up in a different world today,” Germany’s foreign minister said.
Australian Prime Minister Scott Morrison said his country is considering sanctions against 300 members of the Russian parliament over the attack on Ukraine.
Mr Morrison also condemned Russia for the “brutal” and “unprovoked” attack, and said it should withdraw its troops.
Japanese Prime Minister Fumio Kishida condemned Russia’s military actions in the Ukraine and said his country will respond in a speedy fashion in concert with the United States and other allies. “This Russian invasion stands to put at risk the basic principle of international order that forbids one-sided action of force in an attempt to change the status quo. We strongly condemn Russia, and we will respond speedily in cooperation with the US and other Western nations,” he said at his official residence in Tokyo.
China is advising its people in Ukraine to stay home because of ongoing military actions and chaos but made no mention of Russian forces.
The notice issued on its Kyiv embassy’s social media account Thursday said: “Social order is chaotic and out of control, especially in the cities where at times of serious unrest."
It said a person walking on the streets could be a target of attack and traffic could be stopped at any time. It added that people should remain calm and contact local authorities if they come into danger.
China has denounced sanctions against Russia, with which it has increasingly aligned its foreign policy to challenge the West, and blamed the US and its allies for provoking Moscow.
India's Prime Minister Narendra Modi phoned Vladimir Putin on Thursday night and appealed for an “immediate cessation of violence,” his office said in a statement.
Modi also expressed concern over Indian citizens in Ukraine. Officials earlier in the day said some 4,000 out of the 20,000 Indian nationals there had been evacuated.