The French authorities have halted small boats at sea in the Channel on 10 occasions since the spring, officials said on Friday.

Despite claims from the Conservatives and Reform that the French were refusing to intervene in small boat crossings, Maritime Prefect officers were using “intervention tactics” to board or control vessels at sea and take asylum seekers back to France.

The disclosure comes as political parties are once again attempting to seize the initiative over small boats over the summer.

Chris Philp, the shadow home secretary, last week confronted French police on a beach near Boulogne and uploaded footage to X of an officer saying: “Our order is to let them go. We just have to say to them, ‘Don’t do that. It’s dangerous.’”

Earlier this week, Reform MP Lee Anderson visited Calais and said the French police were “literally waving these people on to boats”.

In an unusual intervention, the director of maritime and small boats at Border Security Command, Charlie Eastaugh, said: “The incidents we have seen in the Channel over the last few weeks are a stark reminder of the dangers posed by criminal gangs exploiting people for profit. It is easy to look at out-of-context images and think little is happening to stop these crossings – this is simply not true.

“I know personally how tirelessly French officers have been working to disrupt launches before they reach UK shores. Their efforts include facing violent people with weapons, dispersing huge crowds, arresting smugglers, seizing equipment and collating vital evidence to help our prosecutions.”

Every confrontation with asylum seekers was assessed by commanders as well as individual police officers and gendarmes, who were expected to balance the safety of their officers with that of the public, including large groups of often agitated people and gang members, officials said.

On Sunday, when Andy Burnham visited HM Coastguard in Dover, Border Force officers had been warned that it was a Red Day, when conditions were calm enough for several small boat crossings.

Two small boats attempted to launch from France, but one was intercepted at sea, while the other was halted on land.

Small boats crossing the Channel were down by 43% compared with January to mid-July 2025 – from 21,690 people who crossed last year to 12,469 over the same period this year.

The drop has come despite hot and dry conditions, which are usually associated with an increase in crossings.

UK officials believe that government initiatives to “stop the boats” by financing the French authorities with another £660m in April have disrupted the business model of people smugglers in northern France and reduced the numbers crossing to the UK.

Gangs are adapting their tactics. Boat launches have spread further along the coast, with some leaving from Belgium and others from as far south as Dieppe, which is a journey of 70 miles (113km) to the UK, compared with the Calais to Dover route of 27 miles.

Officials are concerned the trend towards “mega-dinghies” – larger motorised boats – is putting more people at risk. More than 170 migrants were rescued on Tuesday after the boat they were using to cross the Channel caught fire.

The sustained drop in crossings was a welcome development for Burnham, allowing him to focus his early weeks in government on setting out his policy agenda.

Shabana Mahmood, who Burnham has kept in post as home secretary, has been reluctant to celebrate the recent drop because she is conscious the trend could change if there is an increase in arrivals in the late summer and autumn months.