The US president, Joe Biden, joined world leaders arriving in London to pay their respects to the Queen on Sunday, crossing himself as he witnessed her coffin lying in state in Westminster Hall for the last night before her funeral. He followed the prime minister of New Zealand, Jacinda Ardern, the president of Singapore, Halimah Yacob, the president of France, Emmanuel Macron, the head of state of Samoa, Tuimaleali’ifano Va’aleto’a Sualauvi II, and the president of Ireland, Michael D Higgins, among other leaders filing past the coffin alongside members of the public. Public crowds were cleared outside Buckingham Palace in time for hundreds more foreign dignitaries arriving on Sunday evening for a state reception in the picture gallery and state apartments hosted by the King and Queen Consort before the Queen’s funeral at Westminster Abbey at 11am on Monday. They included the president of Israel, Isaac Herzog; the King of Jordan; Olena Zelenska, the first lady of Ukraine; and the European Commission president, Ursula von der Leyen. Biden, who arrived in his “Beast” limousine, said: “To all the people of England, all the people of the United Kingdom, our hearts go out to you. You were fortunate to have had her for 70 years, we all were. The world is better for her.” He described her as “decent, honourable and all about service”. He said he told the King “she’s going to be with him every step of the way”. Hundreds of other guests arrived in coaches with tinted windows laid on by the British government to limit traffic chaos. Among those attending one of the largest gatherings of world leaders in decades were the populist president of Brazil, Jair Bolsonaro, the Canadian prime minister, Justin Trudeau, the president of Rwanda, Paul Kagame, and the leaders of Bangladesh, Ghana and South Africa, as well as the prime minister of Ukraine, Denys Shmyhal. The Princess of Wales met Olena Zelenska in an audience at Buckingham Palace before the reception. David Manning, the former UK ambassador to Washington, described the event as “quite exceptional”. “There is a global response to the passing of the Queen and you see this wish to be associated with her expressing itself in this extraordinary number of visitors to London, heads of state and heads of government,” he said. Leaders signing the book of condolences at Lancaster House before the reception included the prime ministers of Cameroon, Fiji, Guinea Bissau, Jamaica, Lebanon, Mongolia, Niger and Serbia, and the presidents of Armenia, Bulgaria, Ethiopia, Gabon, Georgia, Ghana, Hungary, Nigeria, North Macedonia and Poland. In a statement Trudeau said: “Her presence throughout my life has been constant, inspiring and graceful. As prime minister I benefited from her counsel, thoughtfulness, and curiosity, her sense of humour.” Trudeau held brief talks with the prime minister, Liz Truss, at Downing Street, as did the Irish premier Micheál Martin who, amid tensions over the post-Brexit Northern Ireland protocol, said: “The opportunity is there for us to reset relationships and to be conscious of what we achieved in previous years, the obstacles that were overcome then.” Not attending the funeral, it was reported on Sunday, was Saudi Arabia’s de facto ruler Crown Prince Mohammed bin Salman. It had been thought he might travel to the UK to pay his condolences to the royal family, possibly not at the funeral, but even that was condemned by human rights activists such as Hatice Cengiz, fiance of Jamal Khashoggi, a critic of the kingdom, whose murder, US intelligence concluded, was approved by the crown prince. Saudi Arabia would be represented instead by Prince Turki bin Mohammed al Saud, the source said. Another notable absentee was Vladimir Putin, who was among a small handful of statesmen not invited, including the leaders of Belarus, Myanmar, North Korea and Syria. Questions over the status of the commonwealth realms, where King Charles is now head of state, simmered alongside the gathering. Among those signing the book of condolences set up for world leaders at Lancaster House was Sandra Mason, the president of Barbados, who replaced the Queen as head of state of the Caribbean nation when it became a republic in 2021. The King received condolences from Anthony Albanese, the republican prime minister of Australia who believes his country should have an Australian head of state rather than the British monarch. Asked about whether Australia should become a republic, he said: “I don’t think now’s the time to discuss those issues.” Asked about the King making political interventions, he said it was “important that the sovereign stay distant from party political issues” but said he would be “very comfortable” with him expressing views on the “importance of climate change”. John Kerry, the US climate change envoy, made a similar point, telling the BBC when asked if the King should talk about climate change: “I very much hope so … obviously, in the same way within the constitutional process, but there is no question in my mind … there is a threat to the entire planet, [a] threat to all of our nations and he understands it as well as anybody on the planet.” Ardern said on Sunday that she had no intention of instigating the process of becoming a republic for New Zealand, although she said she expected that would happen in her lifetime. “It’s a transition, but it’s not a jarring transition for New Zealand,” she said. “I think even the Queen herself has observed and acknowledged the evolution over time in our relationships. “My observation is that there will continue to be an evolution in our relationship. I don’t believe it will be quick or soon, but over the course of my lifetime.”