Biden and Sunak meet amid a turning point in the Russia-Ukraine war

When United Kingdom Prime Minister Rishi Sunak visited the White House on Thursday, he hoped a shared perspective on Ukraine and a new push for economic partnership could reinforce what has been a steady, if rather business-like, working relationship.

For President Joe Biden and his team, a relatively low-key prime minister whose term has outlasted a wilting head of lettuce - unlike his predecessor's - is reason enough for celebration.

"There is no issue of global importance, none, that our nations are not leading together and where we're not sharing our common values to make things better," Biden said at the start of a news conference, during which the leaders unveiled a new economic partnership that stopped short of a free trade agreement.

Stability in 10 Downing Street has allowed for better coordination on Ukraine, according to officials, and helped resolve a festering dispute over Northern Ireland trade rules. Sunak's pragmatic approach in some ways mirrors Biden's, even if they hold opposing ideological outlooks.

That made Thursday's meeting in the Oval Office - Sunak's first since taking office - a key moment for the men as they look to deepen their relationship.

As the meeting got underway, Biden thanked Sunak for his partnership on Ukraine, and hailed the relationship between their two countries.

"You know Prime Minister Churchill and Roosevelt met here a little over 70 years ago and they asserted that the strength of the partnership between Great Britain and the United States was strength of the free world. I still think there's truth to that assertion," Biden said.

The talks come at a turning point in the Russia-Ukraine war, following the collapse of the Nova Kakhovka dam and ahead of a widely expected counteroffensive meant to retake territory. The White House said Ukraine would be "top of mind" in Thursday's meeting.

In his news conference, Biden said he was confident that Congress would continue providing support for Ukraine, despite a divide among Republicans.

"The fact of the matter is that I believe we'll have the funding necessary to support Ukraine as long as it takes," Biden said. "I believe that we're going to get that support, it will be real."

As he began his visit in Washington, Sunak said Wednesday it is "too early" to determine what caused the destruction of the dam in southern Ukraine's Kherson region.

"Our military and security services are currently investigating it. But if it is intentional, it would represent an unprecedented level of barbarism," he told Sky News in Washington.

The US and UK have been the leading contributors of military aid to Ukraine, and are coordinating on providing F-16 fighter jets to reinforce long-term deterrence against Russia.

At the same time, Sunak is coming into the meeting with major economic priorities, including a push for closer investment links and more resilient supply chains.

He's also expected to deliver a pitch on making Britain a world leader on developing and regulating artificial intelligence - an area that a British official said was "very much on the prime minister's mind" and that Biden's aides are also watching closely. Because of Britain's exit from the EU, the country has been left out of talks with the US and Europe on the emerging technology. Sunak, who studied in Silicon Valley and views tech as a key issue, is proposing a summit meeting in the fall to discuss AI.

Biden said he was looking at "watermarks on everything that has to do with, produced by AI," and acknowledged the technology's potential for both good but also "great damage."

Ahead of the visit, Sunak cast his economic objectives as directly linked to the security agenda.

"The UK and US have always worked in lockstep to protect our people and uphold our way of life. As the challenges and threats we face change, we need to build an alliance that also protects our economies," he said. "Just as interoperability between our militaries has given us a battlefield advantage over our adversaries, greater economic interoperability will give us a crucial edge in the decades ahead."

Not on the agenda, according to US and UK officials, is a new bilateral trade deal, which had been discussed under former President Donald Trump but now remains on ice.

The broad agenda reflects the typically extensive list of issues between the two nations, whose partnership is nearly always described by their leaders as a "special relationship." Indeed, officials in London and Washington both describe the bond between Biden and Sunak as warm and friendly, as would be expected between the leaders of two countries so closely aligned.

When Biden met Sunak in San Diego earlier this year, he made reference to the condo the Stanford MBA graduate maintains in California.

"That's why I'm being very nice to you, maybe you can invite me to your home," Biden said, perhaps unknowingly raising what has been a controversial issue for the prime minister.

Still, there are undeniable differences between the two men, not least on issues of government economic intervention and the complicated exit of Britain from the European Union.

Few see Biden and Sunak developing a transatlantic friendship akin to Ronald Reagan and Margaret Thatcher, George W. Bush and Tony Blair, or Barack Obama and David Cameron (who called each other "bro").

While the two men have encountered each other several times over the past year, including last month at the Group of 7 summit in Japan, it will be Sunak's first time at the White House for formal talks since he assumed the premiership in October.

Sunak traveled to San Diego in March for a three-way defense summit and met with Biden in Belfast during the president's visit to Northern Ireland in April. Yet that meeting was only a brief chat over tea; Biden spent most of his visit to Ireland exploring his ancestral roots.

There is little question the two men hold very different political ideologies, even if they share a pragmatic, low-drama style - at least compared with their predecessors.

Some members of Sunak's government have openly criticized Biden's Inflation Reduction Act, calling green subsidies included in the package protectionist and warning they would harm American allies. And Sunak has voiced a more limited view of government's role in the economy, akin to his ideological predecessor Thatcher.

Biden's intense interest in resolving a long-festering dispute in Northern Ireland over trade rules has also caused tension. He said after visiting the island in April his trip was intended "to make sure the Brits didn't screw around" with the region's peace structure - a comment that only intensified views among unionists of his pro-Irish allegiances.

There are also generational differences; at 43, Sunak is the youngest leader in the G7 club of industrial democracies while Biden is the oldest at 80.

Still, Sunak has acted as a stabilizing force at 10 Downing Street after a tumultuous period that saw three prime ministers take the job over the course of two months.

Biden and his aides made little attempt to disguise their frustrations with Boris Johnson, a top Brexit proponent. His successor, Liz Truss, was barely in office long enough for Biden to form a full opinion.

By comparison, Sunak has sought to resolve some of the sticky issues that felled his predecessors. He did strike an agreement with the European Union on trade rules in Northern Ireland, though the deal wasn't enough to bring unionists back to a power sharing government

And he has been a staunch proponent of economic and military support for Ukraine, most recently in a pledge to help train Ukrainian pilots on western fighter jets.

One area of discussion likely to arise will be NATO's next secretary general. Sunak has been lobbying for the British defense secretary Ben Wallace, but other candidates are also thought to be under consideration. The job is typically reserved for a European but would require Biden's sign-off.

This story has been updated with additional information.