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Ukraine has agreed with Russian forces to set up a humanitarian corridor to offer civilians a safe route out of the besieged port city of Mariupol.
The city's mayor said authorities hope to move 6,000 people – women, children and the elderly – to safety via the corridor, but cautioned that the agreement was still only a preliminary arrangement and about 100,000 civilians were still in the city.
Thousands of people trapped in the strategic southern city have been told to gather at 2pm local time on Wednesday for evacuation to Zaporizhzhia. The city, which is 220 kilometres north-east of Mariupol, is under the control of the Ukrainian army.
"Taking into account a catastrophic humanitarian situation in Mariupol, we'll be concentrating our efforts in this direction today," Ukraine's Deputy Prime Minister Iryna Vereshchuk wrote on messaging app Telegram.
"We have managed to get a preliminary agreement on a humanitarian corridor for women, children and elderly persons."
However, Ms Vereshchuk said "with regard to the very difficult security situation, changes may occur during the corridor".
Mariupol's mayor, Vadym Boichenko, who has left the city, said 90 buses were waiting to travel to the battleground.
"We plan to send buses to Mariupol but for now it is only a preliminary agreement," Mr Boichenko said on national television.
He said tens of thousands of people had been killed in Mariupol since the start of the war. The number could not be independently verified.
Russia denies intentionally targeting civilians. There was no immediate word from Moscow on whether a humanitarian corridor out of Mariupol had been agreed.
The announcement by Ukraine comes after evacuations from under-fire frontline areas were suspended for the past three days as Kyiv said no agreement could be reached with Russia. President Vladimir Putin’s troops are stepping up their attacks on strategic sites across Ukraine and are engaged in a renewed offensive to capture the eastern Donbas region.
Mariupol, which was a popular seaside resort for Ukrainian families before Russia invaded its neighbour on February 24, is a key target for Moscow. The city, home to 446,000 people before the war, has been subjected to widespread Russian shelling in recent weeks that has left much of it in ruins.
Seizing Mariupol would represent a major win for the Russians and allow them to establish a land bridge between Crimea and Eastern Ukraine. This would allow forces in the peninsula annexed by Russia in 2014 to link up with their comrades fighting alongside separatists in the Donbas, and also deprive Ukraine of much of its coastline.
Moscow has issued a series of ultimatums to Ukrainian forces in Mariupol to lay down arms and surrender. In its latest ultimatum, Russia on Wednesday called on the city’s defenders to surrender by 2pm, and said any troops who laid down arms would be given safe passage out of Mariupol.
The Kremlin's forces are fighting fiercely to oust the remaining Ukrainian troops from their last holdout in the city’s vast Azovstal iron and steel plant, where thousands of soldiers and civilians are holed up.
As the deadline approached, a commander in the plant issued a desperate plea for help, saying his marines were "maybe facing our last days, if not hours".
"The enemy is outnumbering us 10 to one," said Serhiy Volyna, from the 36th Separate Marine Brigade. "We appeal and plead to all world leaders to help us. We ask them to use the procedure of extraction and take us to the territory of a third-party state."
Ukraine says about 300,000 people have escaped the fighting across the country using humanitarian corridors that opened at the start of the conflict.
The Pentagon on Tuesday confirmed Ukraine had received fighter jets and parts to bolster its air force. The US declined to specify the number of aircraft sent nor their origin.
Kyiv has asked its western allies to provide MiG-29s, which its pilots know how to fly and a handful of Eastern European countries have.
The outgoing US ambassador to the UK on Wednesday said Mr Putin had been blindsided by the unity of western leaders when he invaded Ukraine.
Philip Reeker said Mr Putin attacked his neighbouring country “thinking he could divide the West”, but his efforts are not proving fruitful.
Mr Reeker said Nato’s 30 member states had been able to hold raucous debates about policy while also strengthening the alliance.
“It is remarkable to see how the alliance has come together,” he told Sky News.
“Vladimir Putin thought that he would find a divided West, divided alliance, that he would be able to drive wedges. He was sorely mistaken.”
The diplomat said G7 leaders had also been united in their response to Russia's war on Ukraine.
He said each day the world is witnessing Russia undertake “more brutal action in a sort of medieval way” against the former Soviet nation.
“Indeed the West has been remarkably united more than I think many expected under the leadership of leaders like those from the G7 in providing on a daily basis what Ukraine needs to fight this war, what they are doing to defend themselves, their sovereignty,” Mr Reeker said.
He also praised Ukrainian President Volodymyr Zelenskyy for his wartime leadership.
“I saw in Zelenskyy, even as a candidate, someone different who had great qualities of leadership and that’s what we’re seeing now and I think he’s an inspiration, not only to his own people, which is most important, but to so many of us.”