Russia's rouble plunged to a record low on Thursday, while emerging market stocks were set for their worst day since the onset of the pandemic, after Russian forces launched an all-out invasion of Ukraine by land, air and sea.

An adviser to Ukrainian president Volodymyr Zelenskiy said the country is being hit by a second wave of missile strikes, after columns of troops poured across its borders into the eastern Chernihiv, Kharkiv and Luhansk regions, and landing by sea at the cities of Odessa and Mariupol in the south.

The rouble tumbled 2.6%, hovering just above a record low of 89.99 against the dollar hit earlier in the session. Yields on the Russian 10-year benchmark dollar bonds rose to 10.96%, the highest since early 2016.

With investors worldwide fleeing risk assets, the MSCI's gauge for emerging market stocks slumped 4.1% and headed for its worst day since March 2020.

The rouble-denominated MOEX stock index plummeted 30.9%, while the dollar-denominated RTS tumbled 34.1%. Both were set for their biggest one-day percentage declines on record.

Ukraine closed its airspace to civilian flights on Thursday, citing a high risk to safety, while the Interfax news agency said Russia has suspended movement of commercial vessels in the Azov sea until further notice.

The United States and its allies will impose "severe sanctions" on Russia, U.S. President Joe Biden said.

"What's going to happen, only Putin knows. As usual, Russian sources denied any intention to be militarily involved in Ukraine and here we are, in the largest scale military operation in Europe since WWII," said Cristian Maggio, head of strategy at TD Securities.

Maggio added that the Russian rouble and the Turkish lira are likely to take the worst hit.

The lira weakened 3.6% against the dollar to a two-month low.

A war between NATO member Turkey's Black Sea neighbors Russia and Ukraine could harm Ankara's already ailing economy after a currency crisis in December.

Ukraine's central bank banned foreign currency purchases on the interbank market and fixed the official hryvnia exchange rate, while the stock market regulator decided to stop the circulation of all securities.

Safe-haven bets rose, with the dollar strengthening 1% and gold prices jumping to their highest in 17 months.

The Czech crown, the Hungarian forint and the Polish zloty all fell around 1.3% against the euro.