Image: Pope Francis meets King Charles and Queen Camilla during a private audience at the Vatican on 9 April. Pic: Vatican Media/Reuters
The trip came just a week-and-a-half after Buckingham Palace confirmed the King had been taken to hospital following side effects related to his ongoing cancer treatment.
Number 10 has confirmed the prime minister received an invite and will attend the ceremony.
Speaking on Tuesday, Sir Keir said there had been “an outpouring of grief and love” for the Pope.
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Sky News inside Vatican
He added: “I think it reflects the high esteem in which he was held, not just by millions and millions of Catholics, but by many others, across the world, myself included.”
Image: Donald Trump and Pope Francis meet at the Vatican in 2017. Pic: Reuters
The US president was one of the first to confirm he would be flying to Rome, adding he would be joined by first lady Melania Trump.
Writing on his social media platform Truth Social on Monday, he said: “Melania and I will be going to the funeral of Pope Francis, in Rome. We look forward to being there!”
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Trump: ‘Pope Francis loved the world’
The Pope had been critical of Mr Trump at times during his tenure.
In January, he said it would be a “disgrace” if the president went ahead with his crackdown on immigration, telling an Italian television station: “It would make the migrants, who have nothing, pay the unpaid bill.
“It doesn’t work. You don’t resolve problems this way.”
Mr Milei alluded to their “differences” in his tribute to the late Pope, writing: “It is with profound sorrow that I learned this sad morning that Pope Francis, Jorge Bergoglio, passed away today and is now resting in peace.
“Despite differences that seem minor today, having been able to know him in his goodness and wisdom was a true honour for me.”
Image: Pope Francis meets Ursula von der Leyen at the Vatican in 2022. Pic: Vatican Media/Reuters
The EU Commission President confirmed she would be attending after calling Francis a worldwide inspiration.
“He inspired millions, far beyond the Catholic Church, with his humility and love so pure for the less fortunate,” she said in her tribute.
Council President Antonio Costa, Parliament President Roberta Metsola are also expected to attend.
Here are some of the other notable attendees:
• Ireland’s taoiseach Micheal Martin • Spain’s King Felipe and Queen Letizia • Albanian president Bajram Begaj • Angola’s president Joao Lourenco • Austrian president Alexander Van der Bellen • Bangladesh’s chief adviser and interim leader Muhammad Yunus • Belgium’s King Philippe and Queen Mathilde, along with prime minister Bart De Wever • Canada’s governor general Mary Simon • Cape Verde president Jose Maria Neves • Croatia’s president Zoran Milanovic • Cyprian president Nikos Christodoulides • Czech Republic’s prime minister Petr Fiala • Democratic Republic of Congo president Felix Tshisekedi • Dominican Republic’s president Luis Abinader • East Timor’s president Jose Ramos-Horta • Ecuador’s president Daniel Noboa • Estonia’s president Alar Karis • Finland’s president Alexander Stubb • Gabon’s president Brice Oligui Nguema • German president Frank-Walter Steinmeier and outgoing chancellor Olaf Scholz • Greece’s prime minister Kyriakos Mitsotakis • Honduras president Xiomara Castro • Hungary’s president Tamas Sulyok • Italy’s president Sergio Mattarella and prime minister Giorgia Meloni • Latvian president Edgars Rinkevics • Lithuanian president Gitanas Nauseda • Moldova’s president Maia Sandu • Netherlands’ prime minister Dick Schoof • New Zealand’s prime minister Christopher Luxon • Norway’s Crown Prince Haakon and Crown Princess Mette-Marit • The Philippines’ president Ferdinand Marcos Jr • Poland’s president Andrzej Duda • Portugal’s president Marcelo Rebelo de Sousa and prime minister Luis Montenegro • Romania’s interim president Ilie Bolojan • Sweden’s King Carl XVI Gustaf, Queen Silvia and prime minister Ulf Kristersson • Switzerland’s president Karin Keller-Sutter
Image: Pope Francis walks next to Putin at the Vatican in 2015. Pic: AP
The Russian president will not be attending the funeral, the Kremlin has confirmed.
But the controversial leader paid tribute to the Pope, writing a message to Cardinal Kevin Farrell, who is interim chief of the Catholic Church.
“Please accept my most sincere condolences on the passing of His Holiness Pope Francis,” Mr Putin said.
“Throughout the years of his pontificate, he actively promoted the development of dialogue between the Russian Orthodox and Roman Catholic churches, as well as constructive cooperation between Russia and the Holy See.”
Image: Pope Francis and Benjamin Netanyahu meet at the Vatican in 2013. Pic: AP
The Israeli prime minister is not expected to attend, with the country’s ambassador Yaron Sideman going instead.
The Jewish state and the Vatican have had strong relations in the past, with Israel sending a presidential delegation to the funeral of Pope John Paul II in 2005, and Pope Francis visiting Israel in 2014.
But their relationship has deteriorated since the start of the war in Gaza.
A month after the conflict started in 2023, a dispute broke out over whether Pope Francis had used the word “genocide” to describe events in Gaza. Palestinians who met with him said he did, but the Vatican said he did not.
The Pope met relatives of Israeli hostages on the same day.
Israeli officials have since lobbied the Vatican to be more forceful in its condemnation of Hamas.
In January, the Pope called the humanitarian situation in Gaza “shameful”, prompting criticism from Rome’s chief rabbi, Riccardo Di Segni, who accused Francis of “selective indignation”.
Rabbi Di Segni says he will be attending the funeral, despite it taking place on the Jewish sabbath.
Is there a seating plan?
The seats are assigned in advance, with the heads of state sitting in French alphabetical order based on their country’s name, rather than on the individual’s.
This applies to everyone apart from the presidents of Italy and Argentina, who get the best seats because the Pope lived in Italy and was an Argentinian native.