The court's president, Siofra O'Leary, said that "in the past, where states have failed to comply with Rule 39 indications, judges have found that the states have violated their obligations" towards the European Convention on Human Rights.

She said the orders were only made "in exceptional circumstances where there is a real and imminent risk of irreparable harm".

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A Rule 39 interim measure was issued in 2022 to stop a group of migrants being sent to Rwanda. The order was made just hours before their flight was due to take off.

Although that measure expired nearly a year ago, no more flights have been arranged as the Rwanda plan became embroiled in political argument.

Legislation has recently passed through the House of Commons and is currently being debated in the House of Lords.

Rishi Sunak has insisted that, if the legislation is passed, ministers will have the right to order civil servants to ignore those measures.

But Mrs O'Leary said: "The UK has always complied with Rule 39 measures, going back to the 1950s."

Cross-Channel migration is likely to remain at the heart of Britain's political debate.

In Calais, where migrants continue to attempt to reach the UK - and recent bad weather has meant fewer small boat launches - the alternative for migrants is travelling via freight lorries.

Today, as we stood by a road there, a truck made an emergency brake, with a young man mounted on its roof, precariously balanced.

A police car screeched across the vehicle's path, as the youth clambered down, briefly trying to hide between the cab and the trailer, and then ran off.

I caught up with him as he got away. His name was Anil, and he told me he was just 16 years old.

He had come from Sudan, which he said was an unstable country, and wanted to get to the UK to get an education.

"What you're doing is dangerous," I suggested, pointing at the lorries. Anil simply nodded, and walked away.

There is no shortage of lorries around Calais, even more so when the roads are disrupted by farmers' protests, and a growing number of young men, mostly Africans, try to hide aboard them as stowaways on the way to Britain.

But the great majority get caught.

Far, far more people reach the UK in small boats, crossing the Channel in the early hours.

On Thursday morning, we came across a series of police patrols along one stretch of coast that is popular with people smugglers.

On the first occasion, they blocked our car until we had convinced them that we were not involved in smuggling.

On another, as we walked along the beach, a flashlight was shone in our faces as a different team of officers asked what we were doing.

Their job is to try to prevent these crossings from taking place, but the coastline is long and it remains unpredictable when and from where each small boat will launch.