KVIV (Reuters) -Russia gave holdout Ukrainian soldiers an ultimatum on Sunday to lay down arms in the pulverised southeastern port of Mariupol which Moscow said its forces nearly completely controlled in what would be its biggest capture of the nearly two-month war.
Several hours after the 0300 GMT deadline there was no sign of compliance by Ukrainian fighters holed up in the vast Azovstal steelworks overlooking the Sea of Azov.
Having failed to overcome Ukrainian resistance in the north since President Vladimir Putin's Feb. 24 invasion, the Russian military has refocused on the eastern Donbas region where Mariupol is the main port.
The Russian Defence Ministry said its troops had cleared the urban area of Mariupol, which has seen some of the fiercest fighting and worst civilian suffering with bodies littering streets and thousands hunkered down in atrocious conditions underground.
The steelworks, one of Europe's biggest metallurgical plants with a maze of rail tracks and blast furnaces, has become a last stand for the outnumbered defenders.
"The Russian Armed Forces offer the militants of nationalist battalions and foreign mercenaries from 06:00 (Moscow time) on April 17, 2022, to stop any hostilities and lay down their arms," the defence ministry said in a statement.
"All who lay down their arms are guaranteed that their lives will be spared," it said, offering the defending "remnants" a four-hour window to leave the plant without arms or ammunition.
There was no immediate response from Kyiv to the ultimatum, though Ukraine's military said Russian air strikes on Mariupol continued along with assault operations near the port.
Ukrainian President Volodymyr Zelenskiy accused Russia on Saturday of "deliberately trying to destroy everyone" in Mariupol and said his government was in touch with the defenders. But he did not address Moscow's claim that Ukrainian forces were no longer in urban districts.
He said killing his troops would put paid to peace efforts.
"Our soldiers are blocked, the wounded are blocked. There is a humanitarian crisis... Nevertheless, the guys are defending themselves," he told the Ukrainska Pravda news portal.
If Russia's capture of the port is confirmed, it would be the first major Ukrainian city to fall since the invasion and a strategic prize for Moscow: connecting territory that it holds in Donbas with the Crimea region it annexed in 2014.
Russia calls its action a special military operation aimed at demilitarising Ukraine and clearing out what it calls dangerous nationalists.
Russia said Ukraine had lost more than 4,000 soldiers in Mariupol as of Saturday. Kyiv says between 2,500 and 3,000 Ukrainian troops have died so far in the war nationwide
It was not known how many soldiers were in the steelworks. Satellite images have shown smoke and fire coming from the area, which is riddled with tunnels underneath.
Mariupol's defenders have included Ukrainian marines, motorised brigades, a National Guard brigade and the Azov Regiment, a militia created by far-right nationalists that was later incorporated into the National Guard.
Elsewhere around Ukraine, there were reports of more Russian long-range strikes on Sunday.
Local media reported an explosion in the capital Kyiv, though deputy mayor Mykola Povoroznyk said air defence systems had thwarted Russian attacks. The mayor of Brovary city, close to Kyiv, said a missile attack had damaged infrastructure.
And Russia said it had destroyed an ammunition factory near the capital, according to the RIA news agency.
Ukraine resisted Russian ground advances in the early phase of the war, in part by successfully deploying mobile units armed with Western-supplied anti-tank missiles against armoured convoys confined to roads by muddy terrain.
Despite the desperate situation in Mariupol, Ukraine says it has so far held off Russian forces elsewhere in the Donbas regions of Donetsk and Luhansk.
Western sanctions have squeezed Russia's economy but failed to pressure Putin into a withdrawal.
Forthcoming further European Union sanctions will target banks, including major institution Sberbank, as well as oil, the head of the European Commission Ursula von der Leyen told the German newspaper Bild am Sonntag.
