The UK government intends to fly the first planeload of refugees to Rwanda on June 14, after agreeing the plan with Kigali. The UK government is trying to deter migrants from undertaking crossings of the Channel by boat.

A British judge from the London High Court last Friday rejected an emergency bid to block deportation flights of asylum-seekers to Rwanda set to start next week under an agreement with the east African country, ruling politicians must manage immigration policy.

Refugee rights groups and a trade union representing UK Border Force personnel challenged the plan in London's High Court, seeking an injunction against Tuesday's inaugural flight and any beyond then.

They argue that the plan violates asylum seekers' human rights, and say the government cannot justify its claim that Rwanda is a safe destination.

Prime Minister Boris Johnson enthusiastically welcomed the decision by the High Court on Friday. "We cannot allow people traffickers to put lives at risk and our world-leading partnership will help break the business model of these ruthless criminals," he said.

The UN agency's lawyer Laura Dubinsky said it "in no way endorses the UK-Rwandan arrangement".

"UNHCR is not involved in the UK-Rwanda arrangement, despite assertions to the contrary made by the secretary of state," she told the court.