The evacuation of civilians from the besieged southern Ukrainian city of Mariupol has stalled, as Russia's offensive in the east of the former Soviet country continues.
A group of around 100 Ukrainian civilians was expected to leave Mariupol on Monday for the southeastern city of Zaporizhzhya, some 230 km away, but officials said that they had yet to leave, without giving a reason for the delay.
A first group of evacuees left Mariupol on Sunday, but another convoy of civilians from the wider city has been delayed as the buses had not yet reached the agreed pickup point, the city council said.
Petro Andryushchenko, an aide to the city mayor, said Russia has resumed shelling of the Azovstal steel complex, as soon as buses evacuating civilians from the plant had left.
"Yesterday, as soon as the buses left Azovstal with the evacuees, new shelling began immediately," Andryushchenko said.
The Russian army said 126 people had left Mariupol in safe convoys over Saturday and Sunday from the steel works.
On April 25, Russia announced a ceasefire around the giant fortress-like Azovstal steelworks in Mariupol to allow a civilian evacuation from the flashpoint industrial area.
It is estimated by Moscow that some 2,000 Ukrainian soldiers and fighters are holed up inside Mariupol’s Azovstal steel plant. Hundreds of civilians are reportedly sheltering with Ukrainian troops inside the plant.
Those who still remain holed-up in Azovstal's underground bunkers are believed to be running out of water, food and medicine.
"The situation has become a sign of a real humanitarian catastrophe," Ukrainian Deputy Prime Minister Iryna Vereshchuk said.
Since the onset of Russia’s military operation in Ukraine on February 24, more than five million people have fled the eastern European country, and thousands have been killed.
Furthermore, there are increasing concerns for around 100,000 civilians still living in Mariupol, located in southeastern Ukraine and on the north coast of the strategic Sea of Azov.
The ill-fated city has been the scene for some of the heaviest fighting between the two sides.
Russia says it has taken in 140,000 civilians from Mariupol in humanitarian evacuations.
Meanwhile, Ukraine's Defense Ministry has said that fighting is particularly intense the Donetsk and Luhansk regions — collectively known as the Donbas.
"The situation in the Lugansk region can be described in a few words -- active and heavy fighting continues," it added.
Ukraine's army said Russian forces are trying to take over the eastern town of Rubizhne and prepare an assault on Sievierodonetsk.
Luhansk region Governor Serhiy Gaidai also said three people had been killed by shelling over the past 24 hours, adding that the heaviest clashes were taking place around the town of Popasna.
Moscow is pushing for complete control of the Donbas region, where pro-Russian forces already held parts of Luhansk and Donetsk provinces before the military operation.
On Sunday, Russian Foreign Minister Sergei Lavrov said that Moscow only wanted to guarantee the security of pro-Russian Ukrainians in the east and was not demanding that President Volodymyr Zelenskiy surrender as a condition for peace.
"Our aim does not include regime change in Ukraine," Lavrov said in an interview published on his ministry's website.