Ukrainian teenager Mariia Ostapenko and her sister Anastasiia fled the war early in Russia's invasion after bombs destroyed parts of their home city of Dnipro.
They packed their bags and escaped to neighbouring Poland, where hundreds of thousands of other refugees had arrived - but the sisters were lucky, their mother had a friend in the UK who told them about the Homes for Ukraine scheme and organised a sponsor.
They were each offered a room at the home of Jennifer Lowry, 68, shortly after the scheme was announced mid-March, but three months later, following repeated UK government delays, they are stranded in temporary accommodation in Switzerland.
For reasons Mariia and Anastasiia, 23, can't understand, the Home Office won't grant the younger, 15-year-old sister a visa because she is considered an unaccompanied minor.
"They are very vulnerable," Jennifer said, "We are particularly concerned if they have to move elsewhere as visa processing keeps being delayed, they could fall to predators due to being young, and mentally exhausted."
Communication from the UK government has been "very poor" Anastasiia said, and Jennifer says the delays are putting the sisters "at risk". The sisters were left wondering for months about what was happening with their visa application.
In the meantime they've moved from one temporary accommodation to another but their current host in Switzerland can't keep them indefinitely and the sisters are worried about ending up on the streets in a foreign country where they can't speak the language and don't have any friends.
Mariia and Anastasiia are among what is thought to be hundreds of Ukrainian refugees in the same situation, according to the Guardian - they fled their war-torn home country with hopes of finding safety with British families but have found themselves stranded across Europe.
The government says unaccompanied minors are not eligible for the scheme due to safeguarding concerns but has not explained to the sisters what they should do.
A letter from their parent's, giving Anastasiia legal guardianship over her little sister, was presented at Mariia's visa appointment but it appears to have made little difference.
They say they heard nothing for five weeks, until Anastasiia learned how to lodge an official complaint with the British embassy in Paris, which quickly told her thereafter that her visa had been approved but they could not progress with Mariia's.
Speaking to ITV News, the sisters said they don't know what to do next as they appealed to the UK government for compassion.
Anastasiia said: "We don't understand why the legal document [from their parents] making me legal guardian is accepted in countries like Germany, Switzerland and France, but Britain is not accepting it.
"This idea that Britain has to make sure the placement [with a sponsor] is safe actually leaves an underage young person in countries where nobody is waiting for them at all, in comparison to Britain where there is someone happy to take them on."
"This policy actually makes young people more vulnerable," she added.
The sisters travelled thousands of miles across Europe, staying with generous strangers while they waited for their visas to be processed, first from Ukraine to Poland, then to Germany, before moving to Paris and Switzerland.
ITV News reports after more than 50 children were rescued from Dnipro in May:
Mariia, who was still studying at secondary school when her home city was bombed, dreams of starting school in the UK and learning English, while Anastasiia wants to find a job in accountancy after just completing her degree.
They are too afraid to return to Dnipro where their parents remain, because the Russian advance is drawing ever closer, and believe they will soon be homeless if they cannot get to the UK.
Dnipro is just 53 miles away from Zaporizhzhia, a large southern region of Ukraine which Russian forces have controlled large parts of since early in the war.
Their parents are unable to flee, despite the constant threat, because her father is not allowed to leave due to a government direction on fighting-age men, and her mother stayed because she does not have travel documents.
A government spokesperson said "it is tragic that children have been caught up in Putin's war" and suggested the policy on unaccompanied minors was under review, but did not offer a solution for the sisters.
The statement added: "We have a responsibility to keep children safe and as the public rightly expect we have put robust processes in place to protect them once they arrive in the country, working closely with councils throughout.
"Only under-18s who are travelling with, or reuniting with, a parent or legal guardian in the UK are currently eligible for Homes for Ukraine but as we have always said we keep eligibility for all our schemes under review."
ITV News reported on the blast that hit Dnipro days before the girls fled:
A similar case was raised at Prime Minister's Questions last week, with Labour MP Tulip Siddiq telling Boris Johnson about a 13-year-old Ukrainian girl, travelling with her 18-year-old sister, who was forced to return to her besieged hometown in Ukraine.
The older sister had her application approved within three weeks but the younger sister heard nothing back whatsoever, said Mark Falcon who sponsored the pair to live in his family's home.
He told ITV News he's "ashamed and embarrassed" about the UK's handling of the situation, while the girls' parents are "bewildered" by the situation.
They sent a statement in Ukrainian and English giving their consent for the older sister to act on behalf of her younger sister but the application was not accepted by the Home Office.
The older sister was able to resettle at her sponsor's home in London but the teenager's mother was forced collect her and return to Ukraine.
Ms Siddiq asked the PM whether he thinks "sending vulnerable children back to a war zone is the right policy?"
The Labour MP acknowledged "the dangers of child trafficking" but said the Home Office must have a "more sophisticated approach" because its "callous policy has led to a 13-year-old being separated from her 18-year-old sister and forced to return to her war-torn hometown".
She added: "Government is putting many children in grave danger and forcing them to return to areas that are under constant attack by Russia. This cannot by right, and it’s time for the prime minister to show some leadership and sort it out.”
Labour MP Tulip Siddiq asks Boris Johnson about the policy on unaccompanied minors
Responding, the prime minister said: "Of course I understand her indignation about the case that she mentions and I know the home secretary will be looking into it.
"But I have to say that I do think the record of this country in processing so far I think well over 120,000 visas for Ukrainians is very creditable. I thank all the staff who have been involved in that effort."
The UK has received 106,900 visa applications for Ukrainians hoping to enter through the Homes for Ukraine sponsorship scheme, according to the latest Home Office figures, and 48,700 have applied through a separate family scheme.
But of that number, just 88,000 have been granted visas via Homes for Ukraine and just 51,800 have actually arrived in the UK.
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Mr Falcon said the government is "trying to boast about the number of visas processed" but isn't recognising how many are being forced to stay away due to the policy on unaccompanied minors.
More than 14 million people have fled their homes since Russia launched its bloody invasion of Ukraine the United Nations (UN) says.
Almost seven million are in neighbouring countries, while eight million people are displaced inside Ukraine itself.
In total, 77,200 Ukrainian refugees have arrived in the UK - that number is made up of applicants to the sponsorship scheme and the family scheme.
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