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Britain's Queen Elizabeth has made a donation to the Disasters Emergency Committee's Ukraine appeal to help civilians affected by the conflict with Russia.
The charity expressed its thanks to the queen on Twitter for “continuing to support” its work.
The palace has declined to disclose the the amount given, but the committee described it as a “generous donation”.
The organisation, made up of 15 charities, launched its Ukraine appeal on Thursday to provide emergency relief to those who have left their homes after Russian President Vladimir Putin moved in on Ukraine a week ago.
Meanwhile, a senior member of the Ukrainian Red Cross Society described how the nation’s capital city is facing such heavy shelling that air raid sirens have been sounding every 15 minutes.
Olena Stokoz, deputy director general of the charity, outlined the situation in Kyiv while hiding in her house.
“Very heavy shelling is taking place every second … three kilometres from me," Ms Stokez told a Zoom briefing organised by the committee.
“A couple of minutes ago we had a missile hitting civil houses, which is why I’m a bit scared. The situation is very dangerous here and in all parts of Ukraine.
“The most difficult areas, the hottest spots, in Ukraine are in the east, the north, the south and of course in Kyiv.
“We have missile attacks on civilians everywhere and many people have to stay in underprepared shelters almost 24 hours a day as we have air raid sirens every 15 minutes.
“People have to stay there without electricity, food, water, medicine, war clothes and other facilities.
“Other groups of people are trying to leave their homes and migrate either to safer places inside Ukraine or outside Ukraine.”
Funds from the committee's appeal will be distributed to charities working in Ukraine, Moldova, Romania, Hungary, Slovakia and Poland, giving people food, water and shelter.
Saleh Saeed, chief executive of the committee, said it was “absolutely grateful for every single pound” donated. “The more money we raise, the more people that we can reach.”
Every pound from the UK public will be matched by the government through its Aid Match scheme, up to the value of £20 million ($27m).
The UN High Commissioner for Refugees says more than one million people have left Ukraine and sought refuge in neighbouring European countries.
“Many of us would never have envisaged launching a humanitarian appeal in the heart of Europe in 2022,” Mr Saeed said. “Tragically, that’s exactly where we find ourselves today.
“The last time the DEC launched an appeal in Europe was over 20 years ago for Kosovo. That time we thought, ‘Never again’.
“Sadly, we were wrong. Most of the people fleeing are women and children, forced to abandon their homes and loved ones, to find sanctuary in neighbouring countries.
“There are reports of long queues on the border of up to 60 hours in freezing conditions. The unfolding crisis is horrific and heartbreaking.
“But there’s something that we can all do to bring hope. Please donate and help us raise funds and support hundreds of thousands of people who are already fleeing.”
He said the best way for people to help was to donate to fundraising efforts as there was “plenty of aid in the region” but funds were needed to buy it.
Andrew Morley, president and chief executive World Vision International, visited the border crossings in Romania and Moldova this week.
“Thousands of refugees are streaming in and they’re taking up to three days to get across the border," Mr Morley said.
“In Ukraine, all the children I saw crossing the border were in tears. When I looked into their eyes, I saw fear too.
“They were lost, they were scared and when I close my eyes now, their tears are still there.
“To make matters much worse, the sound of conflict can still be heard across the border. This is a constant reminder of the horrors they’re fleeing.”
Television appeals for donations, presented by actors Adrian Lester and Kit Harington, will be broadcast and radio appeals, voiced by David Tennant, will be aired on Thursday.
To donate to the committee’s appeal, visit: www.dec.org.uk.