A LAST-DITCH attempt to block a flight taking migrants to Rwanda on Tuesday has failed following a court battle.

Asylum rights activists and a trade union launched an appeal to prevent a flight – understood to be taking 11 migrants to the African country – from taking off.

Court of Appeal judges rejected the bid which was initiated by the Public and Commercial Services union (PCS), which represents more than 80% of Border Force staff, and charities Care4Calais and Detention Action.

The group unsuccessfully appealed against a High Court ruling on Friday which would allow the first flight to go ahead.

But it is still to be determined whether the policy on the whole is lawful.

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The court decision only addressed specific points from the earlier judgement and the High Court’s Justice Swift made his decision on the “balance of convenience” in favour of the Government.

Raza Husain QC, representing the groups attempting to block the flight, said Justice Swift had made the incorrect decision in backing the Home Office.

But, following an urgent hearing in London, three senior judges have dismissed the appeal, saying there was no error in the decision of Justice Swift.

Lord Justice Singh, sitting with Lady Justice Simler and Lord Justice Stuart-Smith, said the High Court judge had “conducted the balancing exercise properly” and did not err in principle nor in the approach he took.

He added: “He weighed all the factors and reached a conclusion which he was reasonably entitled to reach on the material before him.

“This court cannot therefore interfere with that conclusion.”

Detention Action tweeted in response to the ruling calling it "disappointing" though the organisation noted its larger challenge will be heard in July.

The Scottish Refugee Council described the policy as "state sanctioned violence in action". 

The Home Office has defended the policy and Boris Johnson has said the Government had anticipated “a lot of teething problems” with the policy.

Rory Dunlop QC, representing the UK Government, told the court earlier: “The flight tomorrow is important.

“This is a policy which is intended to deter dangerous and unnecessary journeys, journeys from safe third countries by people who do not need to make that journey to be safe, they can claim in France or wherever it is.

“This is a policy that if it works, could save lives as well as disrupting the model of traffickers.

“Even if we are just talking about cancelling a flight tomorrow, there is prejudice to the public interest, to the enactment of decisions that may have that deterrent effect.”

The High Court heard the UN refugee agency, the UNHCR, has multiple concerns about the system in Rwanda, including discriminatory access to asylum, a lack of legal representation and other “deep-rooted structural problems”.

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Dunlop responded saying that the Home Secretary had “seriously considered” the concerns and had negotiated arrangements in mitigation.

A second case is being heard in the High Court after Asylum Aid, a refugee charity, applied for an urgent interim injunction to stop the Government flying migrants to Rwanda.

Ahead of both hearings, Johnson told broadcasters during a visit to a farm in Cornwall: “I always said that it will begin with a lot of teething problems and you will have a lot of legal action against it and they will try and delay it – that’s inevitable.

“But what we’re trying to do is stop the business model of criminal gangs who are preying on people moving them across the Channel in unseaworthy vessels, risking their lives and sometimes costing their lives.”