Rishi Sunak is set to use a gathering of European leaders to urge cross-continental co-operation to tackle illegal migration.
The Prime Minister will join fellow leaders in Moldova for a meeting of the European Political Community, where he is expected to stress the need to address the issue.
While there, he is expected to announce the start of negotiations on a new returns agreement with Moldova to allow the UK to return foreign nationals who have been found to be in violation of immigration law.
It comes as a similar deal with Georgia enters into force.
The Times reported that Britain will also target Turkey and Bulgaria as part of efforts to tackle small boats crossing the Channel, with the paper saying Border Force has evidence that Turkey has become a main hub for the manufacture of the dinghies used.
Mr Sunak, who will meet with Spanish Prime Minister Pedro Sanchez and Polish Prime Minister Mateusz Morawiecki on Thursday, is also expected to announce an increase in bilateral intelligence sharing with Bulgaria to crackdown on criminal gangs involved in illegal migration.
“Europe is facing unprecedented threats at our borders. From (Russian President Vladimir) Putin’s utter contempt of other countries’ sovereignty to the rise in organised immigration crime across our continent,” Mr Sunak said.
“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.”
In attending the Chisinau summit, Mr Sunak follows in the footsteps of predecessor Liz Truss, who made time to attend the first meeting in the Czech Republic last October during her short-lived premiership.
Spearheaded by French President Emmanuel Macron, the European Political Community is scheduled to hosted by the UK in 2024.
Moldova, which will play host to nearly 50 European leaders for the summit, has accepted thousands of refugees from Ukraine since the Russian invasion last year.
Support for Ukraine and Moldova in the face of Russian aggression is likely to be on the agenda, with Mr Sunak and Mr Morawiecki set to hold a roundtable discussion on security at the summit.
Foreign Secretary James Cleverly in March announced UK funding of £10 million of funding for Moldova, earmarked for economic and governance reforms and including the energy sector.
A Home Office spokesperson said: “We have a close partnership with Turkey when it comes to the shared problem of illegal migration, and we work extensively together to tackle the criminality that enables it.”