FIGHTING

* Russia said a total of 959 Ukrainian fighters, including 80 wounded, had surrendered from the bunkers and tunnels below Mariupol's Azovstal steelworks since Monday.

* Ukraine has said it ordered the Mariupol garrison to stand down but has declined to comment on the fate of the fighters.

* Ukraine's territorial defence force said its fighters had blown up an armoured train carrying Russian troops, but an adviser to President Volodymyr Zelinskiy later said the attack had been confined to rails near the train.

* Russia said it was using a new generation of powerful laser weapons to burn up drones, seeking to counter a flood of Western arms supplied to Ukraine.

DIPLOMACY

* Finland and Sweden formally applied to join the NATO alliance, a decision spurred by Russia's invasion of Ukraine, but face objections from Turkey.

* The United States said it was reopening its embassy in Kyiv.

* Russia said it was expelling embassy staff from France, Spain and Italy in retaliation for similar moves by those countries.

ECONOMY

* US Treasury Secretary Janet Yellen said Western sanctions against Russia had had an enormous impact but the US did not have the authority to seize Russian central bank assets as some had suggested.

* The European Commission unveiled a 210 billion euro plan for Europe to end its reliance on Russian fossil fuels by 2027, and quicken its transition to green energy.

* UN Secretary-General Antonio Guterres said he was in "intense contact" with Russia, Ukraine, Turkey, the United States and the European Union in a bid to restore Ukrainian grain exports as a global food crisis worsens.

* The World Bank said it would make $US30 billion ($A43 billion) available to help stem the food security crisis.

Australian Associated Press