Ukraine has rejected a call to surrender the besieged city of Mariupol after Moscow gave Kyiv until the early hours of March 21 to lay down their arms, according to a Russian state news agency.
Russian Colonel-General Mikhail Mizintsev, head of the Russian National Defence Control Centre, told his counterparts they have until 5am Moscow time (2am GMT) on Monday to respond to his ultimatum, RIA reports.
According to the state controlled media outlet, "the Ministry of Defence wanted to receive a written response from Kyiv" to demands to surrender by that time.
Mariupol has been under siege for weeks and the city now has little food, water and power amid a humanitarian crisis that is increasing pressure on European leaders to toughen sanctions on Moscow.
Russian Colonel-General Mizintsev urged Ukrainian forces in Mariupol: “Lay down your arms.
“A terrible humanitarian catastrophe has developed. All who lay down their arms are guaranteed safe passage out of Mariupol.”
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But Ukraine has rejected Russian calls to surrender the port city.
"There can be no question of any surrender, laying down of arms," the Ukrainska Pravda news portal cited Ukraine's Deputy Prime Minister Iryna Vereshchuk as saying early on Monday.
"We have already informed the Russian side about this."
Mrs Vereshchuk said over 7,000 people were evacuated from Ukrainian cities through humanitarian corridors on Sunday, with more than half escaping from Mariupol.
Many of the city's 400,000 residents remain trapped as fighting rages on the streets around them.
It is unclear what will happen to those who do not surrender in the city, which has suffered terrible losses at the hands of constant Russian bombing over the past three weeks.
Moscow has claimed that the Ukrainian army has been using civilians as "human shields" during the conflict.
In reality the invading Russian forces have been bombarding built up civilians areas at such a pace that most residents were unable to escape before the bombs began to fall.
According to RIA, Colonel-General Mizintsez has also called on the civilians of Mariupol to decide where their allegiances lie.
"Separately, the department appealed to the authorities of Mariupol, noting that now they have the right to make a historical choice: either they are with their people, or with the bandits," RIA reports.
"Otherwise, they face a military tribunal, the Russian ministry stressed."
Russia has said it will open a humanitarian corridor leading both east and west from Mariupol from 10am tomorrow Moscow time.
Colonel-General Mizintsev has urged his Ukrainian counterparts to maintain a ceasefire during that period and for civilians to leave the city.
"From 10am to 12pm - for all armed units of Ukraine and foreign mercenaries without exception, without any weapons and ammunition along the route agreed with Ukraine," he said, RIA reported.
"From 12am simultaneous passage of humanitarian convoys with food, medicines and essentials: from the east — Russian humanitarian convoy, from the west — formed by the Ukrainian side."
Ukrainian civilians may be unwilling to trust the Russians to keep a ceasefire as several attempts to evacuate Mariupol have been scuppered by deadly shell attacks from the invading force.
Colonel-General Mizintsev, without providing evidence, said that Ukrainian "bandits", "neo-Nazis" and nationalists had engaged in "mass terror" and gone on a killing spree in the city.
Ukraine says it is fighting for its existence and President Volodymyr Zelenskiy said on Saturday that the siege of Mariupol was "a terror that will be remembered for centuries to come".
The situation in the eastern port of Mariupol has become increasingly desperate over the past three weeks.
The Russians, determined to seize the city due to its strategic location, have now completely encircled it on both land and sea, stopping vital supplies getting in and people getting out.
While accurate death tolls are difficult to ascertain given that fighting is now raging in the city centre, it is feared thousands have died in Mariupol.
Peter Maurer, the president of the International Committee of the Red Cross, warned that the city was facing a "humanitarian catastrophe".
Two of the worst tragedies of the war so far have taken place in Mariupol.
On March 9, Ukraine said that a Russian strike hit a children’s and maternity hospital, killing at least one child.
This week a bomb was dropped on a theatre, trapping more than a thousand people beneath rubble for days.
According to Mariupol city council and Ukraine’s human rights spokesperson, Lyudmyla Denisova, Russian troops have forced thousands of the city's residents to leave and head to Russia.
“Several thousand Mariupol residents have been deported to Russia,” Denisova said on Telegram.
On Saturday evening Vadym Boychenko, the mayor of Mariupol, said there was now street fighting in the city centre.
