The number of asylum seekers who have received "Rwanda notices", warning that they could be removed to the east African country, has reached almost 1,000, ITV News can reveal.
The charity Care4Calais revealed the number of individuals they were supporting who have been told in writing that their claims could be inadmissible because of evidence they travelled through other safe countries like Italy and France.
The letters state: "We may also ask Rwanda, another country we consider to be safe, whether it would admit you... this will require the sharing of data, including some of your personal information, with the authorities in Rwanda."
It comes as the government faces a major legal and political test on Wednesday, with the Supreme Court ready to rule on the scheme that aims to relocate asylum seekers who arrived by small boat to Rwanda.
The decision follows a majority of judges in the Court of Appeal declaring the policy unlawful (although there was a strong dissenting judgment from the most senior figure in the court).
Steve Smith, CEO of Care4Calais, which is part of the claim- said: "The Supreme Court may be ruling on the Rwanda plan on Wednesday but, regardless of the judges' decision, the plan will continue to be unworkable. It has not acted as a deterrent since it was announced, nor will it in the future."
It's hard to overstate the significance of this decision in the eyes of many MPs on the right of the Conservative Party. To them getting flights to Rwanda is absolutely central to Rishi Sunak's stop the boats policy, and if the government lose they are planning to meet to discuss next steps.
It's likely that they will demand the PM take Britain out of the European Convention on Human Rights - something the former home secretary has argued vociferously for, but her successor, James Cleverly, has suggested within the last six months that this is not necessary.
Even liberal MPs think this is an important issue electorally. One said to me: "I hate the Rwanda policy but I do think Rishi needs to be able to send a flight to Rwanda."
Another argued that if not Rwanda - another country.
Sources in government are not confident about the judgement - although they hope that if they lose it might be a qualified judgment - meaning they can tweak the policy to make it lawful. Or if Rwanda is deemed an unsafe destination (the Court of Appeal felt there was a risk asylum seekers could be returned to their country of origin) that they could choose another country.
And they also stress that there is more to the small boats policy than this idea, stressing the number of crossings have already been cut. Expect plenty of this from Mr Sunak on Wednesday. But they accept it's a significant moment.
If the government wins, they will want to push to get flights headed to Rwanda - a move they claim will act as a deterrent to others coming (although we revealed at the start of this that civil servants say the evidence is not there yet to back up that theory).
There is a very strong sense within the Tory party that this is a critical vote winner - and one that could squeeze the gap with Labour (or blow it wider if things go wrong). They feel that voters see the small boat crossings as a sign that the government has lost control of immigration.
But Smith from Care4Calais fears for those his charity represents. "Successive home secretaries have been driven by a thirst to attack the rights and wellbeing of refugees, and James Cleverly needs to decide whether he wants to be the next.
"Rwanda is not a serious plan to fix the UK’s broken asylum system. It is a cash for people scheme that has already inflicted great pain and torment on the people who have already been threatened with forced removal to Rwanda."
He argued that offering safe passage to victims of torture and modern slavery would stop the crossings.
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