Here are the latest developments in the war in Ukraine:

Ukrainian President Volodymyr Zelensky says the situation in the eastern city of Mariupol is "inhuman", warning the "elimination" of the last Ukrainian troops defending would end peace talks with Russia.

"Russia is deliberately trying to destroy everyone who is there," he says in a video address.

Russia's defence ministry says it has cleared the whole of Mariupol's "urban area" of Ukrainian forces.

They say the only remaining Ukrainian soldiers are in the Azovstal metalworks -- and that their only chance to live is to "lay down their arms and surrender".

Russia steps up air strikes on military facilities in Kyiv, a day after warning it will renew its assault on the capital in response to what it says are Ukrainian attacks on Russian soil.

Moscow says it used sea-based, long-range missiles to hit a tank factory.

Kyiv mayor Vitali Klitschko says at least one person was killed and several wounded.

Ukrainian stamps marked 'Russian warship, Go...!', depicting the Moskva missile cruiser, which has been sunk
Ukrainian stamps marked 'Russian warship, Go...!', depicting the Moskva missile cruiser, which has been sunk AFP / FADEL SENNA

The world should prepare for the possible use by Russia of nuclear weapons, Ukrainian President Zelensky tells journalists Saturday, repeating an earlier warning.

Amid escalating tit-for-tat sanctions, Russia bans entry to British Prime Minister Boris Johnson and several of his senior ministers.

The Kremlin also steps up a crackdown on dissent at home, adding nine prominent Kremlin critics and journalists to its growing list of "foreign agents".

A Russian court orders the pre-trial jailing of a Siberian news editor for alleging that 11 riot police refused to join the military campaign in Ukraine.

Three sappers have been killed and four wounded while trying to clear mines near the eastern city of Kharkiv, Ukraine's interior minister Denys Monastyrsky says.

Russia's defence ministry claims to have shot down a Ukrainian transport plane carrying weapons supplied by western countries in the Odessa region.

Many of the nearly five million people who have fled Ukraine will not have homes to return to, the United Nations warns.

UNHCR, the UN refugee agency, says 4,836,445 million Ukrainians have left the country since the Russian invasion on February 24 -- up 40,200 on Friday's total.