The UK and Moldova are beginning talks on an agreement to return migrants, Prime Minister Rishi Sunak has said.
The planned deal would allow the UK to return foreigners who have breached immigration law and would be similar to an agreement reached with Georgia that is about to come into force.
“Europe is facing unprecedented threats at our borders,” Mr Sunak said, "from [Russian President Vladimir] Putin's utter contempt of other countries' sovereignty to the rise in organised immigration crime across our continent.
“We cannot address these problems without Europe's governments and institutions working closely together. In every meeting, every summit, every international gathering like this, the security of our borders must be top of the agenda.
“The UK will be at the heart of this international effort to stop the boats and defend our national security.”
Mr Sunak is expected to tell the European Political Community meeting in Moldova on Thursday that stopping illegal migration and securing borders should be at the top of the agenda for European leaders.
His speech will come as a deal with Georgia to return migrants comes into effect.
Since 2018, more than 2,000 Georgians have entered the UK illegally.
An agreement with Moldova would have a much smaller impact due to the lower numbers of Moldovans entering the UK illegally – only 17 are known to have done so since 2018.
Migrant crossings into the EU increased by 64 per cent last year, UK government figures indicate.
The EPC was created last year by French President Emmanuel Macron to help leaders from 47 European countries, including those outside the EU, address international challenges.
In Britain, migration is a hot topic. Mr Sunak has promised to cut migration to the UK, especially the number crossing the English Channel in small boats.
In recent weeks, Mr Sunak has agreed on measures to reduce Channel crossings with France and reached a new deal with Albania to return migrants.
He also agreed with EU Commission President Ursula von der Leyen to develop working arrangements between UK agencies and the EU border agency Frontex, now that the UK has left the EU.
Mr Sunak will meet Spanish Prime Minister Pedro Sanchez and Polish Prime Minister Mateusz Morawiecki on Thursday.
He is also expected to announce an increase in intelligence sharing with Bulgaria to clamp down on criminal gangs involved in illegal migration.
Downing Street said the pact would help the Bulgarian authorities “destroy the business model of organised criminal gangs” that profit from illegal migration.
The deal will lead to an increase in intelligence sharing between London and Sofia.
Bulgaria sits on a well-trodden path long favoured by people smugglers and their clients.
The flow of illegal migrants through Eastern Mediterranean and Western Balkans routes has jumped by about 40 per cent since 2021.
Moldova has accepted thousands of refugees from Ukraine since the Russian invasion last year and support for Kyiv and Chisinau in the face of Russian aggression is expected to be on the agenda.
UK Foreign Secretary James Cleverly in March announced £10 million ($12.3 million) in funding for Moldova, earmarked for economic and government reforms, including in the energy sector.