Rishi Sunak has said his absolute priority is to "grip illegal migration" as he sets out plans for a new 72 million Euro (£64 million) deal with France to try to prevent so many boats crossing the Channel.
The prime minister said he had spent more time thinking about this issue than anything else, apart from the Autumn statement since becoming prime minister.
The deal - which was finalised by the Home Secretary Suella Braverman, when she met Interior Minister Gerald Darmanin in Paris this morning - will see a 40% increase in the number of officers patrolling beaches in northern France.
British officers will also be embedded with their French counterparts for the first time.
Mr Sunak said he had raised the issue of small boats bringing people across from Calais to Dover in his first meeting with President Macron last week at Cop27 in Egypt, and the deal showed that the only way to make progress was working with others.
"I’m pleased we’re signing a new deal with the French... But that is not the end of our co-operation and the agreement should be a foundation for even greater cooperation in the months ahead."
'There is no quick fix, no silver bullet' when it comes to migration, says Suella Braverman.
Speaking to reporters on board a plane to Bali for the G20 meeting, the prime minister said: "When it comes to migration more generally I do think that the absolute priority that the British people have right now, as do I, is to grip illegal migration.
"I made a commitment that I would grip it in the summer. And I can tell you all that I've spent more time working on that than anything else, other than obviously the Autumn statement, over the past couple of weeks."
He added: "Look, I've been honest that there's not a single thing to do to fix it and we can't fix it overnight. But there's a range of things I'm working on, including the French deal, where I'm confident we can bring the numbers down over time and that's what I'm going to deliver."
The deal also includes:
investment for port security infrastructure in France to prevent illegal entry via lorries including more CCTV and detection dog teams
more technology such as drones and night vision for officers
funding for reception and removal centres in France to provide alternative options to asylum seekers and migrants.
Sources said there would also be a new task force focused on the recent rise in Albanian nationals coming to the UK, and organised crime groups helping organise journeys. And there would be increased cooperation with other countries.
Enver Solomon, CEO of the Refugee Council, said the deal failed to address the factors behind why men, women and children, take dangerous journeys to reach the UK, arguing it would do little to end the crossings.
“A deal is needed that focuses on creating more safe routes such as family reunion and working with the EU and other countries to find global solutions to share responsibility for what is a global challenge as more people are displaced by war, terror and violence,” said Solomon.
He said the government should be doing much more to create a fair functioning asylum system so there are not more than 120,000 people “stuck in limbo for years” waiting for a decision on their claim.
Data from the Refugee Council shows that a third are waiting up to three years and nearly one in ten up to five years.
Solomon suggested a dedicated task force was needed. He argued that the vast majority of arrivals are “refugees escaping for their lives” and said the problem could not be solved with enforcement measures alone.
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