French officials have made their first interception on the water as part of a new policy aimed at stopping small boats carrying illegal migrants to the UK.

A so-called "taxi-boat" was boarded by French officers on Saturday on the Aa canal in Gravelines, which is on the Channel coast above Calais.

It follows a change of tactics agreed in November following growing pressure from the UK government to step up interventions.

A photograph of the aftermath of the operation obtained by the BBC shows a number of men - apparently people-smugglers - on an inflatable dinghy with the police launch alongside. The inflatable is then towed to the dockside.

The French maritime prefecture declined to comment to the BBC, saying only that there was "an ongoing judicial investigation" regarding the small boat.

France agreed to the new tactics at a summit in the UK last July between President Emmanuel Macron and Sir Keir Starmer.

Until then French police had only intervened to stop small boats as they were being prepared for launch on beaches. Intervening at sea was judged to be too dangerous.

But smugglers' gangs learned to avoid police by using "taxi-boats", which enter the water some distance away and then travel along the coast picking up groups of migrants who themselves enter the water to get aboard.

According to an official French documents, this method was proving extremely effective, with an 81% success rate in 2025.

The number of migrants who reached the UK from France rose last year from 36,566 in 2024 to 41,472, but it was lower than the peak of 45,774 in 2022.

After the July 2025 agreement to start on-water interventions, there were more delays because of worries about the risk to life, and about officers' liability to prosecution were migrants to die in an operation.

These concerns appear now to have been addressed. Under the terms of engagement, gendarmes will only intervene to stop "taxi-boats" before they take on migrants – and not when they are fully charged.

This seems to have been the procedure used in Saturday's operation.

Police suspected that the inflatable, which was moving down the canal to its mouth at the sea, was about to be used for picking up migrants, so they moved to arrest the men on board.