Macron-Starmer visit: What difference will 'one in, one out' small boats deal make?

One of Sir Keir Starmer's most memorable pre-election promises was that he would "smash the gangs" of people smugglers sending people across the English Channel on small boats.

That hasn't happened yet. More than 21,000 people have arrived in the UK on small boats so far this year, more than 50% higher than at this point in any previous year.

"We all agree that the situation in the Channel cannot go on as it is," said Sir Keir earlier on Thursday, speaking alongside French President Emmanuel Macron.

"We're bringing new tactics into play, and a new level of intent, to tackle illegal migration and break the business model of the criminal gangs," he added.

So what are those new tactics?

For starters, the French have changed rules that had limited them from engaging with migrant boats once they had entered the sea.

They've now started using knives to puncture inflatable boats in shallow waters.

But what has grabbed most attention is a scheme to exchange illegal migrants in the UK with asylum seekers in France, that Sir Keir says will start "in the coming weeks".

The plan (just a pilot at this stage) is that the UK will send a number of people - reportedly starting at around 50 a week - who have arrived in the UK after crossing the Channel, back to France.

And for each person sent back to France, France will deliver to the UK an asylum seeker with a family connection in Britain. Only people who have not previously attempted to enter the UK illegally will be eligible.

How much of a difference will that make to the overall numbers?

If it starts at 50 people, not much.

More than 200 migrants are estimated to have arrived in the UK on small boats on the day of this announcement alone. And that's not unusual.

Since the start of March an average of over 1,000 people have arrived every week. Sending 50 of them back would represent less than 5% of that total.

In fact, it would be equivalent to less than one full boat. The average number of migrants per boat increased to 64 in June, the highest level on record. Twenty boats a week arrived on average.

Can it be a deterrent?

So the reported numbers are small in comparison, but whether the policy will act as a deterrent is a different question.

Oxford University's Migration Observatory says "there is some evidence that suggests a returns deal could affect asylum seekers' decisions to come to the UK from Europe, including in small boats".

"If the government wants a returns deal to deter people from crossing to the UK, the number of people transferred would be extremely important," it adds.

Starmer said that the number of people transferred between the two countries would "ramp up" if the pilot is successful. How they would define success, or how much it'll rise to, or when, is unclear at the moment however.

The Migration Observatory says: "If the risk of being transferred was very small, it is more likely that prospective asylum seekers would not know about the policy or would be willing to take the risk. How high this proportion would need to be is impossible to forecast."

The scheme would however represent a significant rise in the number of asylum-related returns that the government delivers currently.

In 2024, 2,627 asylum seekers were forcibly returned - usually to their home country - by the UK.

Adding 50 people a week to that figure would almost double it.

Although of course each return ("one out") would be reciprocated by an additional arrival ("one in") from France. And there are still questions about how the policy would work in practicality - how the migrants would be selected, and what the UK would do if faced with legal challenges.

Sir Keir said that revealing how they would select who might be returned to France might "undermine" how the scheme would operate.

The Migration Observatory says: "Even if an agreement is reached that allows a significant number of people to be returned to the EU, it is uncertain how many would be transferred in practice.

"As with the Dublin system [the EU principle that asylum seekers can be returned to the first EU country they entered] in the past, there may be further administrative barriers to returns, such as legal challenges to removal."

Small boat arrival numbers v other types of migration

Since 2020, crossing the Channel in a small boat has been the most common way to arrive illegally in the UK, overtaking smuggling via lorries for example.

Small boat arrivals are also certainly responsible for most of the emotion and political attention attached to illegal migration.

But they are probably not responsible for the majority of people in the UK who don't have a legal right to remain here.

We can only say "probably" because data on "visa overstayers" - people who arrived in the UK legally but ended up staying longer than they were entitled to - has not been published since 2020.

But the last time the figures were published, the number of visa overstayers was up near 100,000, more than twice as high as the record number of annual arrivals in small boats - 45,755 in 2022.

This pilot scheme is not designed to tackle that form of illegal migration, although Mr Macron did say that he and Sir Keir had discussed it as part of the summit.

All of that illegal migration pales into insignificance compared with the overall net migration, however, despite a recent fall. This is the figure that previous administrations failed to "get down to the tens of thousands" as they had pledged to.

Between 2023 to 2024 it halved, from 860,000 to 431,000 - mainly thanks to changes made to rules about workers and students bringing dependants under Rishi Sunak's premiership.

We get to that "net" figure by taking away the 517,000 people who left the UK in the last year from the 948,000 who arrived in the same period.

The 50 people a week - to be returned to France, and indeed received from France - that the pilot scheme is reported to be starting off with is equal to 2,600 people a year moving in either direction.

That would be just 0.5% of the total number of people leaving the UK each year, and 0.27% of the total arriving.

It's appropriate that when we plot that on a chart, it appears so low that it might as well be on the floor.

While the numbers reported at the moment are a relative drop in the ocean compared with overall migration figures, Sir Keir will be hoping that the fact he is taking visible action against the problem will bring him a political benefit while Nigel Farage's Reform party lead in the polls.

Whether such a small proportion can serve as a deterrent, or even prove that raising the number higher would help, is something that we will observe in the months to come.

The Data and Forensics team is a multi-skilled unit dedicated to providing transparent journalism from Sky News. We gather, analyse and visualise data to tell data-driven stories. We combine traditional reporting skills with advanced analysis of satellite images, social media and other open source information. Through multimedia storytelling we aim to better explain the world while also showing how our journalism is done.

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