Keir Starmer and Emmanuel Macron held a major press conference this afternoon.
The Prime Minister and the French President held the press conference as part of Mr Macron's landmark state visit - announcing a landmark deal on migrant returns and updating on progress towards peace in Ukraine.
The pair embraced and shook hands out side Downing Street this morning, before entering No10 for the Franco-British summit where they are expected to locked in talks over migration. Mr Starmer is hoping the French president will sign up to a "one in, one out" deal. It would mark the first returns deal with France for the first time since Brexit in a desperate bid to stop small boat crossings.
The two leaders will also take part in a phone call of the "coalition of the willing" leaders on the future of the Ukraine conflict.
Speaking at the start of the summit this morning, Mr Starmer said the UK will address illegal migration with "new tactics" and a "new level of intent". The Prime Minister said: "In uncertain times, we achieve more by strengthening our relationship with our allies, so that is what today is all about working together on the priorities that we share as two nations."
Attendees at the meeting in Downing Street included Home Secretary Yvette Cooper, Chancellor Rachel Reeves and Energy Secretary Ed Miliband.
Follow live updates below...
"Of course, it's a pilot," Starmer says of the process that will start in the coming weeks.
"It's important that it works - but if it does work, what it does is break the [gang's business] model."
He won't go into detail about who will be selected for return as it risks undermining the process.
Starmer says: "Irregular migration is a serious problem across the world...but it requires a serious, pragmatic response, not the politics of easy answers."
Starmer says it's important for leaders like him and Macron - two social democrats - can actually deal with the problem, adding a dig at Nigel Farage for "just taking pictures."
There is "no greater demonstration" of the importance of the UK-France relationship than the agreement to coordinate their nuclear deterrents, Mr Starmer said.
He said of the Northwood Declaration: "There is no greater demonstration of the importance of this relationship, and while we stand together for our collective defence, we must also deliver a defence dividend for working people so we've agreed a deeper industrial partnership today to bring our defence industries closer than ever before."
Macron thanks Starmer and the King for the hospitality he's been shown during the state visit.
"Times have been changing," he said. "And our partnership must also evolve."
He said the future holds more sophisticated threats to both nations.
"That's why we have taken the measures we have taken."
"Previous governments tried and failed to deliver results like this," Starmer says.
"We can deliver them now because we've taken the time to do the real work, the quiet, serious work."
He adds that Britain and France, by working together, can be a "force for good" in an uncertain world.
Starmer says the meeting of the coalition of the willing included representatives from the US for the first time.
It wasn't Trump, but Keith Kellogg, one of the US President's envoys, who joined the call.
Starmer says the UK will overahul the joint expeditionary force, and that Britain and France have signed an agreement confirming cooperation between the two countries' nuclear deterrents.
Starmer says a deal has been struck to return migrants crossing the Channel back to France "in short order".
In return, the UK will accept an asylum seeker into the UK from France through safe and legal means for each one that is returned.
Starmer says regardless of the small boats crisis, the UK must remain a "haven" for genuine asylum seekers.
He said: “This is our plan together: hard-headed, aggressive action on all fronts to break the gangs’ business model, secure our borders and show that attempting to reach the UK by small boat will only end in detention, failure and return."
He wants to make clear that crossing the channel in a small boat will only lead to "failure, detention and return".
"We serve our people better...make our nations stronger and more secure, if we work together," Keir Starmer told Emmanuel Macron at the top of the press conference.
"Today our task is to look forward. To deliver a step change in this relationship ...and get the results that people want to see."
Starmer says small boats are "acutely a crisis for our two nations" - run by organised gangs and leading thousands to their deaths.
"We are determined to end this vile trade," he said.
The Coalition of the Willing will have a new permanent headquarters in Paris, with plans in place for a future coordination cell in Kyiv, as command structures for the future reassurance force are finalised.
Following agreement on command structures for the force, leaders agreed that planning should continue on an enduring, business as usual footing, to ensure that a force can deploy in the days following the cessation of hostilities.
Following agreement on command structures for the force, leaders agreed that planning should continue on an enduring, business as usual footing, to ensure that a force can deploy in the days following the cessation of hostilities.
That will include a 3-star multi-national operational headquarters in Paris, led by the UK and France, to oversee all tactical and operational arrangements.
The headquarters, which will rotate to London after the first 12 months, will allow partners to contribute forces flexibly and deploy military teams for different operational strands of work.
When the force deploys, a co-ordination cell, headed up by a UK 2-star military officer will also be set up in Kyiv.
Emmanuel Macron told the coalition call: "We have a plan that is ready to go and initiate in the hours after a ceasefire."
Italian prime minister Giorgia Meloni and Ukraine's president Mr Zelensky joined the call from the Ukraine Recovery Conference in Rome.
Also dialled in was Keith Kellogg, a retired US general and special presidential envoy to Ukraine, as well as Lindsey Graham, a Republican US senator mobilising sanctions against Russia, and his Democrat colleague Richard Blumenthal.
Mr Zelensky told the meeting that Ukraine needs the US "very much" because of its sanctions against Russia, as well as military support.
The Prime Minister also suggested the coalition of the willing would shift more of its focus towards ensuring Ukraine is in the "strongest possible position" in the event of a ceasefire, alongside being prepared to police a peace deal.
Sitting alongside Sir Keir was Defence Secretary John Healey, national security adviser Jonathan Powell, and Admiral Sir Tony Radakin, chief of the defence staff.
Me Macron was joined by Mr Healey's counterpart Sebastien Lecornu, and high ranking officials.
Sir Keir and Mr Macron were earlier given a tour of Nato's maritime command centre, also based at Northwood.
European plans for a peacekeeping force to aid Ukraine once the war ends are now "mature" after months of planning, Keir Starmer said.
French president Emmanuel Macron meanwhile described the so-called coalition of the willing as "ready to go" once a ceasefire is agreed.
Planning for the coalition began in March following a summit at Lancaster House in central London, with the aim of policing a future end to the war in Ukraine.
That summit saw European allies rally to the Ukrainian cause, following Volodymyr Zelensky's tumultuous visit to the White House at the end of February.
Under the coalition plans, troops from France and the UK would be placed in Ukraine, while other countries would provide logistical support, all with the aim of deterring further Russian aggression.
European leaders have insisted the arrangement would be dependent upon an American "security guarantee", likely in the form of air support, something Donald Trump has been unwilling to openly say he would provide.
Mr Starmer and Mr Macron dialled into a call with allies who make up the coalition from the UK's military headquarters at Northwood in north-west London, where they made the announcement that preparations for the force are complete.
Speaking during the call on the last day of Mr Macron's state visit to the UK, the Prime Minister said: "I am very pleased to say today that these plans are mature and we are putting them on a long-term footing."
The press are currently waiting in a warm holding area at the undisclosed location.
French and British correspondents are pushing for info about what's going on in the rooms nearby, but we're currently in the dark.
The level of co-operation with France has "never been stronger", Downing Street has said as Sir Keir Starmer seeks to hammer out a migration deal with Emmanuel Macron.
A No 10 spokesman said he would not speculate on the details of a potential agreement and that "innovative" approaches and a "targeted international response" were needed to tackle illegal migration.
"Our co-operation with France has never been stronger," he said.
Asked if Sir Keir Starmer still thinks the situation in the Channel is deteriorating, he said: "We've been consistently clear that the numbers are unacceptable."
He welcomed the "changing tactics" of French authorities in recent weeks.
He continued: "Clearly, more work needs to be done, as I say, we will approach that, whether that is investing in border security command, whether that is working with our international allies. We're clear that this is an international problem, cracking down on these gangs cannot be done singularly."
Keir Starmer and Emmanuel Macron are currently thought to be on a zoom call with the European leaders who make up the 'coalition of the willing' - and who have vowed to support and defend Ukraine against Russia's invasion.
It comes after Ukraine's president Volodymyr Zelensky spoke at a summit in Rome.
“Partners need to be faster with investments in weapons production and technology development,” Zelensky said at the summit. “We need to be faster with sanctions and put pressure on Russia so that it feels the consequences of its terror.”
