LONDON – After the bonhomie and banquets of a formal state visit, Prime Minister Keir Starmer and President Emmanuel Macron are turning to a topic that has stymied successive British and French governments: how to stop migrants from crossing the English Channel in small boats.

At a U.K.-France summit on Thursday that caps Macron’s three-day stay, senior officials from the two countries will try to seal deals on economic growth, defense cooperation and – perhaps trickiest of all – unauthorized migration.

Macron and Starmer also will visit a military base and dial in to a planning meeting of the “ coalition of the willing, ” a U.K.- and France-backed plan for an international force to guarantee a future ceasefire in Ukraine.

During a meeting inside 10 Downing St. on Wednesday, the two leaders agreed that tackling small boat crossings “is a shared priority that requires shared solutions, including a new deterrent to break the business model” of people-smuggling gangs, Starmer’s office said.

It said they would aim for “concrete progress” on Thursday.

Channel crossings are a longstanding challenge

Britain receives fewer asylum-seekers than Mediterranean European countries, but sees thousands of very visible arrivals each year as migrants cross the 20-mile (32 kilometer) channel from northern France in small, overcrowded boats.

About 37,000 people were detected crossing the channel in 2024, and more than 20,000 made the crossing in the first six months of 2025, up by about 50% from the same period last year. Dozens of people have died trying to reach the English coast.

Britain and France agree the dangerous and unregulated crossings are a problem, but have long differed on how to address it.

The U.K. wants France to do more to stop boats leaving the beaches, and has paid the Paris government hundreds of millions of pounds (dollars, euros) to increase patrols and share intelligence in an attempt to disrupt the smuggling gangs.

“We share information to a much greater extent than was the case before,” Starmer told lawmakers in the House of Commons on Wednesday. “We’ve got a new specialist intelligence unit in Dunkirk and we’re the first government to persuade the French to review their laws and tactics on the north coast to take more effective action.”

Macron says Britain must address “pull factors” like the perception it is easy for unauthorized migrants to find work in the U.K. Many migrants also want to reach Britain because they have friends or family there, or because they speak English.

Solutions have proved elusive

As far back as 2001, the two countries were discussing ways to stop migrants stowing away on trains and trucks using the tunnel under the channel.

Over the following years, French authorities cleared out camps near Calais where thousands of migrants gathered before trying to reach Britain. Beefed up security sharply reduced the number of vehicle stowaways, but from about 2018 people-smugglers offered migrants a new route by sea.

“You see that pattern again and again, where smuggling gangs and migrants try to find new ways to cross from France to the U.K.,” said Mihnea Cuibus, a researcher at the University of Oxford’s Migration Observatory. “The authorities crack down on that, and then gradually you see migrants and gangs try to adapt to that. And it becomes a bit of a game of cat and mouse.”

Cooperation on stopping the boats stalled after Britain’s acrimonious split from the European Union in 2020, but in the past few years the countries have struck several agreements that saw the U.K. pay France to increase police and drone patrols of the coast.

Britain’s previous Conservative government came up with a contentious plan in 2022 to deport asylum-seekers arriving by boat to Rwanda. Critics called it unworkable and unethical, and it was scrapped by Starmer soon after he took office in July 2024.

Britain hopes for a returns deal with France

Starmer is staking success on closer cooperation with France and with countries further up the migrants’ routes from Africa and the Middle East.

British officials have been pushing for French police to intervene more forcefully to stop boats once they have left the shore, and welcomed the sight of officers slashing rubber dinghies with knives in recent days.

France is also considering a U.K. proposal for a “one-in, one-out” deal that would see France take back some migrants who reached Britain, in return for the U.K. accepting migrants seeking to join relatives in Britain.

Macron said the leaders would aim for “tangible results” on an issue that’s “a burden for our two countries.”

Cuibus said irregular cross-channel migration would likely always be a challenge, but that the measures being discussed by Britain and France could make an impact, “if they’re implemented in the right way.

“But that’s a big if,” he said.