These are the key events so far on Tuesday, March 22. Get the latest updates here.

Fighting

• The focal point is Mariupol, a strategically important southern port that has suffered some of the heaviest bombardment since Russia invaded. Many of its 400,000 residents remain trapped as fighting rages around them.
• Russian artillery continues to pound the eastern cities of Kharkiv, Sumy, and Chernihiv.
• A Ukrainian news outlet is reporting air raid sirens “in almost every region” of the country.
• The Pentagon says Russia is boosting air and sea military operations in Ukraine, flying more than 300 missions in the past 24 hours.

Refugees

• Nearly 3.5 million people have left Ukraine while 6.5 million people have been displaced internally, the United Nations says. More than 8,000 people were evacuated on Monday.

Sanctions

• The European Union cannot agree on whether or how to impose sanctions on Russia’s lucrative energy sector. Germany says the bloc is too dependent on Russian oil for that.

Diplomacy

• Peace talks have resumed but there is no sign of significant progress to end the conflict.
• Ukrainian President Volodymyr Zelenskyy says he is ready for talks with Russian counterpart Vladimir Putin “in any format”.
•  US-Russia ties are on the brink of collapse, Russia’s foreign ministry says, summoning the US ambassador after Biden called Putin a “war criminal”.
• The UN General Assembly is expected to vote again this week on a motion criticising Russia for the humanitarian crisis in Ukraine.

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