United Kingdom

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A source said the plane, which was stood ready on a Ministry of Defence runway at Boscombe Down in Amesbury, would not be departing due to "last minute interventions from the European Court of Human Rights".

Home Secretary Priti Patel said the government "will not be deterred from doing the right thing and delivering our plans to control our nation's borders" despite the first flight to Rwanda being stopped.
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Earlier this evening, it was confirmed that two individuals due to be sent to the east African country had had their exit from the UK postponed following last-ditch efforts by lawyers.

It was understood the European Court, which granted an urgent interim measure blocking the removal of one Iraqi detainee, was considering a number of further requests.

A total of seven individuals were believed to have been due to board the flight before the successful interventions were made.

https://news.sky.com/story/first-deportation-flight-to-rwanda-halted-after-last-minute-legal-appeals-home-office-confirms-12634130