An adviser to Ukraine's president says about 40 people have been killed so far in the Russian attack on the country. Oleksii Arestovich, an adviser to President Volodymyr Zelenskyy said Thursday that several dozen people have been wounded.

 Stocks plunged and oil prices surged by more than 5 per barrel Thursday after President Vladimir Putin launched military action in Ukraine, prompting Washington and Europe to vow sanctions on Moscow that may roil the global economy.

The Russian military says it has knocked out Ukraine's air defence assets and airbases.

Russian troops launched their anticipated attack on Ukraine on Thursday, as President Vladimir Putin cast aside international condemnation and sanctions, warning other countries that any attempt to interfere would lead to consequences you have never seen .

US Secretary of State Tony Blinken on Tuesday cancelled his scheduled meeting with his Russian counterpart Sergei Lavrov later this week in protest against what he said was the beginning of Russia's invasion of Ukraine.

Moscow: Russian lawmakers on Tuesday authorised President Vladimir Putin to use military force outside the country - a move that could presage a broader attack on Ukraine after the US said an invasion was already underway there.