UK signs Kensington Treaty with Germany on immigration enforcement

17 July 2025 saw the signing of the Kensington Treaty between UK Prime Minister Keir Starmer and his German counterpart, Friedrich Merz. The first bilateral treaty signed between the two nations since WWII addresses cooperation in spheres of defence, economic growth and security.

The treaty contains a landmark commitment from Germany to introduce a new law, criminalising the facilitation of illegal migration to the UK, to be adopted by the end of the year. Germany’s current law only criminalises the facilitation of illegal migration to countries within the European Union, which, following Brexit, excludes the UK.

The law aims to dismantle people-smuggling networks and prosecute those involved. The proposals aim to provide authorities with the tools needed to investigate and take action against warehouses and storage facilities used by migrant smugglers to conceal small boats used in illegal crossings to the UK. In cooperation with European partners, the National Crime Agency has in the last 18 months seized more than 600 boats, with the expectation that the introduction of this law by Germany will see this figure increase.

The challenge of curbing Channel crossings has increased pressure on the UK Government, with the Shadow Home Secretary, Chris Philp, saying that “The crisis in the Channel continues to spiral” when commenting on a recent report stating that over 21,000 people had crossed the English Channel since January 2025 (marking a 56% increase from the same period last year).

However, Kier Starmer will be keen to hail the Kensington Treaty a success, and evidence of real progress from the Joint Action Plan on Irregular Migration, a framework for the future relationship between the UK and Germany for enhanced co-operation on irregular migration and combatting organised crime, introduced in December 2024.

Key elements of the Joint Action Plan, such as strengthening the operational capabilities of UK and German law enforcement to tackle migrant smuggling and cementing the UK and Germany’s commitment to working with European and regional partners on irregular migration, are echoed in the Kensington Treaty.

The Treaty comes hot on the heels of the UK’s pilot ‘One in, one out’ migrant deal, agreed with French President Emmanuel Macron. The policy will see people arriving by small boat being returned to France in exchange for an equal number of asylum seekers, who will come to the UK via a new legal route.

Chris Philp, Shadow Home Secretary, challenged the effectiveness of the pilot deal, claiming it will only result in the return of “one in every 17 illegal immigrants arriving”. Critics have also drawn comparisons between this deal and the Conservative’s Rwanda scheme, which was scrapped by Kier Starmer after the general election.

Nevertheless, this decision marks a shift in French policy, as for the first time since Brexit, France have confirmed their willingness to accept the return of migrants. Starmer will be reassured by Merz’s suggestion that “The cooperation between the United Kingdom and France <…> has to be complemented by an agreement that we aim to achieve between the three of us: UK, Germany, France”, and will be keen to see it as a clear intention of further cooperation between the European nations.

The Kensington Treaty marks a shift in British-European diplomacy, and aims to establish a unified front among the participating states to tackle illegal migration.

How Gherson can assist

Gherson’s Immigration Team are highly experienced in advising on UK visa matters. If you have any questions arising from this blog, please do not hesitate to contact us for advice, send us an e-mail, or, alternatively, follow us on X, Facebook, Instagram, or LinkedIn to stay-up-to-date.

The information in this blog is for general information purposes only and does not purport to be comprehensive or to provide legal advice. Whilst every effort is made to ensure the information and law is current as of the date of publication it should be stressed that, due to the passage of time, this does not necessarily reflect the present legal position. Gherson accepts no responsibility for loss which may arise from accessing or reliance on information contained in this blog. For formal advice on the current law please do not hesitate to contact Gherson. Legal advice is only provided pursuant to a written agreement, identified as such, and signed by the client and by or on behalf of Gherson.

©Gherson 2025