Russian leader Vladimir Putin unleashed a full-scale invasion on Thursday that has killed dozens of people, forced more than 50,000 to flee Ukraine in just 48 hours and sparked fears of a new Cold War in Europe.

European Commission chief Ursula von der Leyen said the sanctions "will have maximum impact on the Russian economy and the political elite".

Ukrainians picked up weapons when boxes of them were dumped from trucks and handed out to Ukraine's new volunteer defense units on day two of Russia's invasion.

Germany could send an infantry company with around 150 soldiers and more than a dozen Boxer wheeled armoured vehicles in a timely manner, according to a package that the military has put together for Defence Minister Christine Lambrecht, the media outlet said.

Macron said after a summit of EU leaders that "while condemning, while sanctioning" it remained useful "to leave this path open so that the day when the conditions can be fulfilled, we can obtain a cessation of hostilities".

Speaking to reporters, Morrison said Australia is working with the North Atlantic Treaty Organization to provide "nonlethal military equipment and medical supplies to support the people of Ukraine."

In a speech from the White House, Biden said four more banks -- including the two biggest, Sberbank & VTB -- would be hit with sanctions by Western sanctions. In addition, export controls slapped on sensitive components will "cut off more than half of Russia's high-tech imports."

In a day of intense fighting, Russian missiles and shelling rained down on Ukrainian cities, forcing civilians to seek shelter on metro systems, with others displaced by deadly airstrikes.

The soldiers, which would take part in NATO's operations in Estonia, would be deployed in the first half of March, the country's chief of defence told journalists at a press briefing.

Zelensky said Thursday Kyiv's forces were fighting invading Russian troops for control of the Chernobyl plant, the site of the world's worst nuclear disaster.

"I told him to leave," the man in his 30s sobbed, next to the twisted ruins of a car.

"As a result of strikes carried out by the Russian armed forces, 74 Ukrainian military ground facilities were destroyed," said Igor Konashenkov, a defence ministry spokesman.

“Stop the war. War brings misery to mankind and puts the world at risk,” President Jokowi tweeted on Thursday.

Putin announced the launch of a major military offensive and ground troops crossed into the country from several directions on Thursday, with explosions heard in Ukraine's capital, Kyiv.

Russian President Vladimir Putin authorised a military operation in eastern Ukraine in what appeared to be the start of war in Europe.

"President Putin, in the name of humanity, bring your troops back to Russia," Guterres said, speaking after an emergency meeting of the Security Council on Ukraine.

Weeks of intense diplomacy and the imposition of Western sanctions failed to deter Putin, who had massed between 150,000 and 200,000 troops along the borders of Ukraine.

The sounds were heard shortly after Russia announced a military operation in Ukraine.  

In an address aired shortly after midnight Zelensky said Russia could invade Ukraine "any day now" and, addressing the Russian people, said whether that happens "depends on you."

Safe Airspace, which was set up to provide safety and conflict zone information for airlines after Malaysia Airlines flight MH17 was shot down over eastern Ukraine in 2014, said it had increased its risk level to "do not fly".

During an appearance on a rightwing radio program, the hosts asked Trump about Putin recognizing two breakaway regions in eastern Ukraine as independent.

"Now that we see the invasion is beginning and Russia has made clear its wholesale rejection of diplomacy, it does not make sense to go forward with that meeting at this time," Blinken said.

The situation over Ukraine escalated when Russia, which has been massing troops near Ukraine for months, recognized on Monday the two self-proclaimed republics of Donetsk and Luhansk as independent and ordered troops to be deployed there for "peacekeeping" missions.

As leader of the G20, President Joko “Jokowi” Widodo has called for the swift yet measured handling of the Ukraine crisis to avoid catastrophe at a time of urgent collaboration.

Speaking at an emergency meeting of the UN Security Council, the Russian ambassador, Vassily Nebenzia, also warned Western powers to 'think twice' and not worsen the situation in Ukraine.

Earlier, the Kremlin leader recognised the independence of two rebel-held areas of the Donetsk and Lugansk regions of Ukraine, paving the way for an operation to deploy part of the potential invasion force he has massed around the country.

"We are confronted with a very, very dramatic situation," France's ambassador to the United Nations Nicolas de Riviere told reporters before entering the council chamber.  France was among a handful of nations that called the emergency session at the instigation of Ukraine.

It was that intelligence that gave US President Joe Biden the confidence to say Friday he was "convinced" his Russian counterpart Vladimir Putin had decided to invade, the reports said.

A cross-border media investigation broke Sunday claiming that Switzerland's second-largest bank had held tens of billions of dollars of ill-gotten funds, claims based on an insider's massive data leak.

The two leaders accepted the idea of such a meeting after French President Emmanuel Macron held separate phone talks with both of them. Preparations will be made when US Secretary of State Antony Blinken and Russian Foreign Minister Sergey Lavrov meet Thursday in Europe.