This Maxar satellite shows burning apartment buildings in northeastern Mariupol. AFP

The city council said the pounding was turning Mariupol into the "ashes of a dead land." Russia's RIA news agency said Russian forces and units of Russian-backed separatists had taken about half of the city, citing a separatist leader.

The plight of civilians in Mariupol, home to 400,000 people before the war, grew ever more desperate. Hundreds of thousands are believed to be trapped inside buildings, with no access to food, water, power or heat.

"There is nothing left there," Ukrainian President Volodymyr Zelenskiy said in a video address to Italy's parliament on Tuesday.

An Ukranian woman lifts her daughter as she arrives at an arrival centre in the BOK sport hall, Budapest. Reuters

Deputy Mayor Sergei Orlov told CNN the city was under a full blockade and had received no humanitarian aid.

"The city is under continuous bombing, from 50 bombs to 100 bombs Russian aircraft drops each day...a lot of death, a lot of crying, a lot of awful war crimes," Orlov said.

Mariupol has become the focus of the war that erupted on Feb. 24 when Russian President Vladimir Putin sent his troops over the border on what he calls a "special military operation" to disarm Ukraine and replace its pro-Western leadership.

WASTELAND

The Mariupol city council gave no details of casualties or damage from the latest bombing. A Reuters team that reached a Russian-seized part of the city on Sunday described a wasteland of charred apartment blocks and bodies wrapped in blankets lying by a road.

Ukraine says Russian shells, bombs and missiles have struck a theatre, an art school and other public buildings, burying hundreds of women and children sheltering in cellars.

Children sit on a bus bound for Germany after fleeing from Mariupol. Reuters

Deputy Prime Minister Iryna Vereshchuk, speaking on Ukrainian television on Tuesday, demanded the opening of a humanitarian corridor for civilians. She said at least 100,000 people wanted to leave Mariupol but could not.

Ukraine also accused Russia of blocking humanitarian access to Kherson, which lies northwest of Crimea and is the only provincial capital it has captured. The Foreign Ministry said Kherson's 300,000 residents were running out of food.

Pentagon spokesman John Kirby told Fox News on Tuesday the Russians were frustrated by their lack of progress.

"They did not expect the Ukrainians to fight back this hard. They thought it would be a lot easier to just walk into Kyiv in a couple of days and take the capital city," he said. 

Ukraine appeals to Russia over Mariupol as humanitarian concerns grow

Ukraine appealed to Russia on Tuesday to allow humanitarian supplies into Mariupol and let desperate civilians out of the besieged city, which President Volodymr Zelensky said had been devastated by Russian bombardment.

Multiple explosions and rising smoke are seen around an industrial compound in Mariupol.

Officials in Mariupol say the port city on the Sea of Azov, which has a peacetime population of 400,000, has no food, medicine, power or running water.
Mariupol's plight highlights what an international aid official in Ukraine said was the breakdown of the country's humanitarian system.

"There is nothing left there," Zelensky said of Mariupol in a video address to the Italian parliament. As he was speaking, the city council said Russian forces had dropped two large bombs on Mariupol but gave no details of casualties or damage. Reuters could not independently verify the report. Russia did not immediately comment on it.

"Once again it is clear that the occupiers are not interested in the city of Mariupol. They want to level it to the ground and make it the ashes of a dead land," the council said in a statement.

Russia denies targeting civilians and blames Ukraine for the repeated failure to establish safe passage for civilians out of Mariupol. Ukraine defied an ultimatum for the city to surrender by dawn on Monday as a condition for Russian forces to let civilians leave safely.

"We demand the opening of a humanitarian corridor for civilians," Deputy Prime Minister Iryna Vereshchuk said on Ukrainian television on Tuesday.

Vereshchuk said Mariupol was the main focus of government evacuation efforts but that Russian forces were also preventing humanitarian supplies reaching residents of the occupied southern city of Kherson. She gave no details.

Steve Gordon, humanitarian response adviser at international aid agency Mercy Corps, expressed concern about the vulnerability of supply chains in Ukraine.
"We know that most municipalities in areas seeing the most intense fighting don’t have more than 3-4 days worth of essentials like food," Gordon, who is in Ukraine, said in a statement issued by Mercy Corps.

"The reality is that right now the humanitarian system is entirely broken down. We are not seeing a high-functioning, coordinated international aid effort covering the whole of Ukraine, like we often see in other conflict zones."

Only a few thousand civilians have managed to flee Mariupol, including a convoy witnessed by Mercy Corps.

"The cars are all taped together with duct tape and plastic, packed with 7-8 people in each car. Many of the cars say 'child' on the window in the hopes that this would prevent them from being attacked," he said.

"Some have belongings strapped to the roof but many have nothing and you can tell people had to leave everything behind."

Reuters