Russian spies have been linked to the people-smuggling gangs trafficking migrants into Europe and across the English Channel.
Bulgaria’s Home Secretary, Daniel Mitov, claims his government has evidence of direct links between Russia’s foreign intelligence agency and the organised crime gangs helping people to cross Europe illegally.
He also suggested left-wing humanitarian groups were in direct contact with the smuggling gangs.
It comes as ministers from Europe will gather alongside Sir Keir Starmer in London next week to discuss plans to stem irregular migration through the Western Balkans.
“Illegal migration inflows are an instrument for hostile regimes to destabilise the European Union and the United Kingdom,” Mr Mitov told the Times.
The latest small boat Channel crossing figures meanwhile showed a total of 369 people made the perilous journey in seven boats on Saturday, bringing the total for the year so far to a record 36,734, according to Home Office figures.
The total is 82 short of the total for the whole of 2024 which was 36,816.
Ministers returned 16 more people to France this week, taking the number deported under the deal to 42, the Home Office said.
It is understood the number of migrants arriving from France under the “one-in, one-out” treaty struck by Sir Keir and Emmanuel Macron now stands at 23.
Home Secretary Shabana Mahmood described the latest deportation efforts as the “largest return flight under our historic deal with the French”.
"For many years, illegal migrants entered our country with no consequence,” she said.
"This is the largest return flight under our historic deal with the French.
"And it sends a warning to those considering entering this country illegally: if you come here by small boat, you can be sent back.
"This is just the beginning - I will scale up these removals to France. And I will do whatever it takes to secure our borders."
More flights are expected to take place in the coming days and week.
The returns deal signed earlier this year is aimed at creating a disincentive for the Channel crossing.
Ms Mahmood met her counterparts from the western Balkans in London on Wednesday, ahead of the Prime Minister’s gathering next week.
International policing efforts are attempting to crack down on smuggling gangs who have plotted trafficking routes through the region.
