The British Home Office announced today that it has detained the first illegal immigrants who arrived in the United Kingdom on small boats and who are due to return to France under the French-British agreement that came into force yesterday.

“The people who arrived in the UK on a boat yesterday afternoon were taken into custody. They will be settled in administrative detention centers awaiting deportation,” the Home Office said in a statement, without specifying their number.

The new Franco-British agreement, announced during French President Emanuel Macron‘s official visit to the United Kingdom in July, aims to discourage those who want to cross the Channel in unsafe and overcrowded boats with the help of smuggling networks.

According to London, the first deportations to France are expected to take place “in the coming weeks.”

The UK will send France within three days the names of the migrants detained that it wants to deport. French authorities will have 14 days to respond, according to the British Home Office.

“When I say nothing will stop me from making our borders secure, I mean it,” British Prime Minister Kire Starmer said via X, who is under pressure to curb migrant arrivals.

A record number of more than 25,400 people have entered the UK via this sea route since the start of the year, registering a 49% year-on-year increase.

The agreement is based on the one-to-one principle. France will accept migrants arriving in the UK on small boats whose asylum claim was not accepted there. At the same time, London will accept people in France who have made a claim on an online platform, giving priority to those with family ties to the UK.

This platform is currently active on the UK government website.