Lviv: Ukrainian President Volodymyr Zelenskyy said Russian forces not only blocked a humanitarian convoy trying to reach besieged Mariupol with desperately needed supplies on Tuesday but took captive some of the rescue workers and bus drivers.
He said the Russians had agreed to the route ahead of time.
We are trying to organize stable humanitarian corridors for Mariupol residents, but almost all of our attempts, unfortunately, are foiled by the Russian occupiers, by shelling, or deliberate terror, Zelenskyy said in his night time video address to the nation.
Deputy Prime Minister Iryna Vereshchuk said the Russians seized 11 bus drivers and four rescue workers along with their vehicles. She said their fate was unknown. The figures couldn't immediately be confirmed.
Intense Russian air strikes are turning besieged Mariupol into the "ashes of a dead land", the city council said on Tuesday, as street fighting and bombardments raged in the port city.
Hundreds of thousands are believed to be trapped inside buildings, with no access to food, water, power or heat. Both civilians and Ukrainian troops were coming under Russian fire, said regional governor Pavlo Kyrylenko.
Russian forces and Russian-backed separatist units had taken about half of the port city, normally home to around 400,000 people, Russia's RIA news agency said, citing a separatist leader.
More than 7,000 people were evacuated from Mariupol on Tuesday, but about 100,000 remain in the city in inhuman conditions, under a full blockade, without food, without water, without medicine and under constant shelling, under constant bombardment, Zelenskyy said.
Before the war, 430,000 people lived in the port city on the Sea of Azov.
Mariupol has become the focus of the war that erupted when Putin sent his troops over the border on what he calls a "special military operation" to demilitarise Ukraine and replace its pro-Western leadership.
The city's capture would allow Russia to link areas in the east held by pro-Russian separatists with the Crimean peninsula, annexed by Moscow in 2014.
The United Nations human rights office in Geneva said on Tuesday it had recorded 953 civilian deaths and 1,557 injured since the invasion. The Kremlin denies targeting civilians.
Millions have fled abroad, according to the United Nations, leaving Eastern Europe scrambling to provide them with care, schools and jobs.
The United States plans to launch an effort this week to make it easier for some to enter after only a handful of refugees were admitted in the first two weeks of March, according to three people familiar with the matter. Moscow denies forcing people to leave, saying it is taking in refugees.
In Kherson, a city under Russian control, Ukrainian officials said Moscow's forces were preventing supplies from reaching civilians.
"Kherson's 300k citizens face a humanitarian catastrophe owing to the Russian army's blockade," foreign ministry spokesperson Oleg Nikolenko said on Twitter.
Russia did not immediately comment on the situation in Kherson.
Zelenskyy warned the crisis in Ukraine, one of the world's biggest grain exporters, would bring famine elsewhere.
"How can we sow (crops) under the strikes of Russian artillery?" he told Italian lawmakers.
'Confrontational' talks on
Talks between Ukraine and Russia are confrontational but moving forward, President Volodymyr Zelenskyy said on Wednesday, as the West plans to announce more sanctions against the Kremlin amid a worsening humanitarian crisis.
In an early morning address, Zelenskyy held out hope for negotiations, which have yielded little since the Feb. 24 invasion began.
"It's very difficult, sometimes confrontational," he said. "But step by step we are moving forward."
Russian President Vladimir Putin's incursion into Ukraine has forced more than 3.5 million to flee, brought the unprecedented isolation of Russia's economy, and raised fears of wider conflict in the West unthought-of for decades.
Western nations plan to heap more pressure on the Kremlin.
Alongside European leaders, U.S. President Joe Biden is expected to announce new sanctions against Russia and new measures to tighten existing ones when he visits Brussels this week.
The United States is preparing sanctions on more than 300 members of Russia's lower house of parliament as soon as Thursday, according to The Wall Street Journal, which cited unnamed officials and internal documents.
Biden's Europe trip is also set to include an announcement on joint action to enhance energy security on the continent, which is highly reliant on Russian gas, and a visit to Poland to show solidarity with Ukraine's neighbour.
Having failed to seize the capital Kyiv or any other major city with a swift offensive, Russia is waging a war of attrition that has reduced some urban areas to rubble and prompted Western concern that the conflict could escalate, even to a nuclear war.
Russia's combat power in Ukraine has declined below 90% of its pre-invasion levels, a senior U.S. defence official said on Tuesday, without providing evidence. If confirmed, it would suggest heavy losses of weaponry and growing casualties.
(With inputs from AP via PTI, Reuters.)