The leaders of France and Britain aim to iron out differences over migration and deepen military ties on Friday amid the war in Ukraine after years of bickering over Brexit.
Rishi Sunak, who became Britain's prime minister in October, is hoping to capitalise on renewed goodwill with fellow former investment banker Emmanuel Macron to end years of arguing over issues ranging from migration to fishing.
The meeting in Paris will be the first summit of Europe's two main military nations - both permanent members of the United Nations Security Council and nuclear powers - in five years.
Ties which have often been rocky since Britain voted to leave the European Union in 2016 have been fortified by the countries' support for Ukraine since Russia's invasion.
"The partnership the UK and France share runs deep," Sunak said on Twitter. "From tackling illegal migration to driving growth in our economies to defending our common security, when we work together we all benefit. It's in that spirit I'm looking forward to meeting @EmmanuelMacron today."
A French presidential adviser said the summit's priority was for the two NATO allies to reconnect.
The meeting also comes as relations between Britain and the EU have also improved in light of the Windsor Framework - a new agreement with the bloc aimed at fixing problems with Northern Ireland's post-Brexit trading arrangements.
Later this month, King Charles will also travel to France on his first state visit as monarch.
Sunak and Macron struck up a personal rapport at the COP27 summit in Egypt in November during their first face-to-face meeting, two weeks after Sunak became prime minister, with their warm relationship labelled "Le Bromance" in British newspapers.
Sunak has sought a reset with France after relations soured under his predecessors Boris Johnson and Liz Truss, and is looking to work with Paris on tackling the large numbers of migrants that arrive in southern England in small boats.
In November, Britain and France signed an agreement worth 72 million euros ($74 million) to ramp up efforts to stop illegal migrants from making perilous journeys across the Channel.
The issue will be high on Britain's agenda in particular. Sunak wants more done to stop the crossings.
The Times newspaper said he would announce Britain was providing funding to France to invest in police, security and intelligence. The payments were expected to exceed 200 million pounds over three years, the report said, citing unnamed sources.
Speaking to the BBC from Paris ahead of the talks, Foreign Secretary James Cleverly confirmed Britain would be discussing giving more money to France, but did not give further details or amounts.
The two countries have been criticised by non-governmental organisations for their handling of the issue.
"The relentless intimidation, violence and degrading treatment perpetrated in the name of 'border enforcement' by both countries has proven entirely ineffective at stopping people from arriving in northern France or attempting to cross the Channel to find refuge in the UK," Medical charity Medecins Sans Frontieres said in an open letter to the leaders on Thursday.
Britain on Tuesday set out details of a new law barring the entry of asylum seekers arriving in small boats across the Channel, a proposal some charities say could be impractical and criminalise the efforts of thousands of genuine refugees.
Asked about the British government's announcement on small boats, French officials said it did not change the fact that since Brexit, there was no bilateral deal on how to readmit migrants in France.
"At this stage we see no major impact for French coasts. It's not as if we had a legal instrument since Brexit that helped us regulate the flow of migrants between the two coasts," one official said.
France is keen to deepen defence ties, including through the joint training of Ukrainian soldiers, and also want to make their two competing future fighter jet programmes, FCAS and Tempest, compatible, Elysee advisers say.