Biden has arrived in London for a two-day visit in honor of the Queen

Biden is joining the leaders of dozens of other nations in praising the late sovereign, who he said reminded him of his mother after meeting him last year.

On Sunday afternoon, President Jill Biden and first lady Jill Biden will pay tribute to the Queen, whose coffin has been in state in Westminster Hall, before signing a book of condolence and attending a reception for visiting leaders hosted by Britain’s new King Charles. III.

For Biden, it is a moment to reflect on a monarch who embodied his commitment to public service and whose life charted the major historical events of the past 100 years.

Biden and the Queen first met in 1982 when, as a young senator, Biden’s Irish-American mother instructed him, “Don’t bow down to her.”

He did not bow down then, nor when he met the Queen as President last year when he attended a Group of 7 summit in England. But his respect for a woman who had a unique consistency on the world stage in the last century was clear.

“She was a great lady. We’re so glad we got to know her,” Biden said the day she died.

The Queen’s surprise decision to travel to the Cornish coast last year to meet world leaders at the G7 summit was a sign of her desire to remain engaged in global affairs.

Earlier that week, when he hosted Biden and first lady Jill Biden for tea at Windsor Castle, he asked them about two authoritarian leaders, Chinese President Xi Jinping and Russian President Vladimir Putin, the president told reporters.

“He was so curious. He wanted to know everything about American politics, what was going on. So he put us at ease,” Jill Biden said in an interview on NBC.

At Sunday evening’s reception, Biden will see Charles for the first time since he became king. The two men have previously met and spoke on the phone last week.

Like the Prince of Wales, Charles Biden was also a passionate campaigner for some of the issues he has defended, including combating climate change. It remains to be seen how the new King will participate in these matters in the future.

Relatively close in age — Charles is 73, Biden 79 — the two men have shared decades of experience in the public eye before assuming their roles as current heads of state.

In his call with the king, Biden “conveyed the great admiration the American people have for the Queen, whose dignity and constancy have deepened the enduring friendship and special relationship between the United States and the United Kingdom,” the White House said. “President Biden expressed desire to continue close relationship with King.”

Security in the British capital is at its highest level in memory as Biden and dozens of other world leaders gathered to remember the late queen, joined by 13 sitting US presidents during her tenure.

White House aides have declined to provide specific security details for the president’s visit, but say they are working closely with their British counterparts to ensure the president’s security requirements are met.

Plans for the Queen’s funeral have been in the works for years, allowing US advisers to know exactly what will happen in the coming days, while taking security precautions. The White House said it only extended invitations to the president and first lady, managing to slim down the American footprint.

Biden traveled with his national security adviser, communications director and other personal aides on Air Force One to London.

When reports emerged last week that world leaders would have to travel by bus to the funeral, US officials were skeptical and dismissed the suggestion that Biden would travel to Westminster Abbey by bus.

In 2018, when other world leaders traveled together in a bus to a World War I memorial in Paris, then US President Donald Trump got separated in his vehicle. The White House explained at the time that the separate trip was due to “security protocols.”

The Queen’s death came at a time of economic and political turmoil in the United Kingdom. The new Prime Minister, Liz Truss, took office after months of uncertainty following the decision of her predecessor, Boris Johnson, to step down.

Truss has invited visiting world leaders to meet individually at 10 Downing Street this weekend. In the role for just over a week, it will be the first time Truss has come face-to-face with many of his overseas counterparts.

Although her office initially said Biden would be among the leaders visiting Downing Street, it was later announced that Truss and the president would meet for formal bilateral talks on the sidelines of the United Nations General Assembly in New York on Wednesday.

A host of problems are testing the “special relationship” between the US and the UK, which has been repeatedly announced in the days since the Queen’s death.

The longtime royal died just two days after Truss traveled to Scotland’s Balmoral Castle to formally accept the Queen’s appointment as prime minister. Since then, the country has been in a formal period of mourning.

Truss inherited a deep economic crisis, fueled by high inflation and rising energy costs, which has fueled fears that the UK could soon enter a protracted recession. The challenges have been compounded by Russia’s invasion of Ukraine, which has caused volatility in the oil and gas markets.

Few in the Biden administration shed tears over Johnson’s resignation – Biden once described him as a “physical and emotional clone” of Trump – as the US and UK became more united in their approach to Russia under his leadership.

White House officials expect cooperation under Truss to continue, even as he comes under pressure to ease economic pressures at home.

It is less certain, however, whether Truss’ hard-line approach to Brexit is straining relations with Biden. The President has taken a personal interest in the specific issue of the Northern Ireland Protocol, the post-Brexit agreement that requires additional checks on goods moving between Northern Ireland and the rest of the UK.

The rules were designed to keep the border between Northern Ireland and the Republic of Ireland open and prevent a return to sectarian violence. But Truss wants to rewrite those rules, causing deep anxiety in both Brussels and Washington.

Biden, who often refers to his Irish ancestry, has made his opinion clear on the issue, although he does not directly implicate the United States. Democrats in Congress have also expressed concern that the steps could reignite the conflict in Northern Ireland.

In their first phone call as peers earlier this month, Biden raised the issue with Truss, according to the White House. A US readout of the conversation said they discussed “a shared commitment to protecting the gains of the Belfast/Good Friday Agreement and the importance of reaching a negotiated agreement with the European Union on the Northern Ireland Protocol”.