Sean Coughlan
Royal correspondent

King Charles has sent a private message to Pope Leo XIV, congratulating him on his election. Buckingham Palace says the King and Queen sent Pope Leo their "sincere good wishes for his Pontificate".

King Charles and Queen Camilla had held one of the last high profile meetings with his predecessor, Pope Francis, visiting him in the Vatican in the weeks before his death.

The service has started with a prayer led by the Pope, to acknowledge sins and ask for God's forgiveness.

The congregation has joined him in singing and taking part in the liturgy.

The new Pope has just been led into the Sistine Chapel and begun to conduct Mass.

He kissed the altar and walked around it once with incense.

Image source, Reuters

We're starting to get video from inside the Sistine Chapel for the first time, where the 130-plus strong contingent of cardinals have gathered for Pope Leo's first Mass as pontiff.

We're now just minutes away from Pope Leo XIV leading a Mass in the Sistine Chapel, marking the first time he'll do so as the leader of the Catholic Church.

Our correspondents are poised to bring you updates from the scene outside the chapel in St Peter's Square, and you can also follow the Mass live by pressing watch live above.

Visitors are marking this historic day by posing with today's newspaper in front of St. Peter's Basilica. The front page shows a picture of the new Pope's balcony address.

Image source, Getty Images

Image source, Reuters

Image source, Reuters

"Oh my God it's Rob - it's never gonna be the same." This was the reaction of the Pope's brother, Louis Prevost, when he heard the news.

Louis says that his brother has always had a clerical temperament, even as a child. Playing together as boys, he would want to roleplay as a priest.

Mike Wendling
Reporting from Chicago

Image source, BBC/Mike Wendling

As news spread of Pope Leo's election in his hometown of Chicago, there was palpable excitement for not only the first North American Pope, but a South Side Chicagoan.

"When they said the new Pope was an American, I flipped out, I said 'no way'!" said Mary Simons, a nearby resident.

A small crowd had gathered at the church where he attended mass as a child to take in the occasion.

Charleen Burnette, one of Pope Leo's former classmates, remembered him as a "quiet, kind, gentle, wicked-smart kid".

But despite his Chicago roots, some are confident that Pope Leo XIV will follow in the footsteps of his predecessor and be a voice for all.

"He might be from Chicago, but he will be a Pope for the whole world," said Father Gregory Sakowicz.

MORE: Chicago celebrates hometown Pope

Image source, Reuters

Our colleagues from BBC Newsday have interviewed the president of the Catholic Theological Union in Chicago, where Robert Prevost studied.

Sister Barbara Reid says she is thrilled to hear he has been elected Pope, but also says it is strange for those who knew him from the past.

"I'm struggling to call him Pope Leo XIV, we knew him as Bob," she tells the programme.

Reid describes him as a "person with a global perspective and with a heart for the whole church", citing his time as a bishop in Peru, where he also holds citizenship.

On Pope Leo's character and traits, she describes him as an "extremely bright, very intelligent, very astute", as well having a "very large heart for the people who are most needy".

Image source, Getty Images

It's been less than 24 hours since plumes of white smoke emerged from the chimney on the Sistine Chapel, indicating that a new pope had been elected.

Pope Leo XIV - the name US-born Robert Prevost has taken - greeted worshippers on the balcony of the Vatican not long after that smoke had disappeared into the clear blue sky above St Peter's Square.

If you're just joining us now, here's what you need to know for the rest of the day:

• Pope Leo XIV is due to hold his first Mass as pontiff in the Sistine Chapel at 11:00 local time (09:00 GMT, 10:00 BST)
• He is the first North American to be elected leader of the Catholic Church
• In his first remarks as pope, the Chicago-born pontiff spoke in Spanish and Italian, delivering a message of "peace" and "unity"
• Catholics and world leaders are continuing to share their congratulations to the new pontiff, including US President Donald Trump who calls his election a "great honour"

Sarah Rainsford
Eastern Europe correspondent, in St Peter's Square

This morning in and around St Peter’s Square, life is returning to normal in many ways - with pilgrims processing towards the basilica and tourists heading for the museums.

But for Catholics there is big change, and they’re still absorbing what it means to have an American pope.

We chatted to one Italian lady who was out walking her Basset Hound, and she was pretty happy.

She tells me Prevost was American, but a Pope of the world.

“He travelled all over,” she points out. “And he spoke Italian and Spanish in his address from the balcony, not English.”

Yesterday, when the name of the cardinal who’d just been elected was announced, there was confusion and surprise - even shock - from many of the people I was standing close to.

Even when Leo XIV came out onto the balcony, most in the crowd didn't recognise him.

That will all change. The souvenir stalls here are just setting up this morning. They haven’t got their “American Pope” T-shirts ready just yet, but it's only a matter of time.

Image source, BBC/Sarah Rainsford

We're now seeing some pictures come through that take a step back in time.

The images show Robert Prevost - who has chosen the name Leo XIV on becoming the new pontiff - shaking hands with many of his predecessors in years gone by.

Image source, Reuters

Image source, Reuters

Image source, Vatican Media

Over on the BBC's Today programme, they've just finished catching up with a man whose friendship with the new Pope dates back to before the millennium.

Reverend William Lego tells the BBC that one of the traits that stood out in Pope Leo, even back in 1966, when the two were going through high school and then college together, was his patience.

"He doesn't make quick decisions," Lego says, explaining how Robert Prevost, as he was then known, would take his time to "gather information" and "pray over stuff".

Lego also says that he's "always been centred on working with the poor" and believes that even back then he showed signs of being a "good leader".

Being a fellow Chicagoan, Lego chuckles when he reflects how locals in the city have been celebrating the news with memes - including one that shows Pope Leo changing the eucharist to deep-dish pizza.

Once chosen, a new pope is asked what he wishes his papal name to be.

For more than 500 years, popes used their own names, but this changed to symbolic names to simplify their given names or to refer to previous pontiffs - which is why most popes in history have chosen the name John.

We don't yet know why Pope Leo chose his name, but it's one of the most popular ones previous popes have selected.

It's not only the fact that Pope Leo XIV is the first North American pope that sets him apart from his predecessors, explains Austen Ivereigh, a Catholic writer and commentator.

"But when he speaks English, he'll be doing so with a Chicago accent," Ivereigh tells BBC Breakfast this morning. "And that matters."

The papal biographer tells BBC that his American dialect will make him more relatable to an American audience - which "means they can't dismiss him in sometimes the way they tried to with Francis" - who spoke English with an Argentine accent.

He also notes that by selecting an American pope, the Conclave's choice reflects the shifting geopolitical powers of the day.

"The assumption has always been, America being the superpower, you couldn't have a pope who's also an American," he says.

"But of course, America's role in the world has now changed."

Image source, EPA-EFE/Shutterstock

Guillermo D Olmo and Helen Sullivan
Reporting from Lima and Sydney

Image source, Getty Images

Halfway through Leo XIV's first speech as pope, which he delivered in Italian, he stopped and asked if he might say a few words in Spanish.

Smiling, he continued: "A greeting to all and in particular to my dear Diocese of Chiclayo, in Peru."

The first US pontiff is a citizen of Peru and has spent much of his life there, travelling between the two countries for decades until 2014, when Pope Francis appointed him bishop of the Chiclayo Diocese in the country's north.

On Thursday, Peruvians rejoiced at the appointment of one of their own to the highest position in the Catholic Church.

Standing near Lima's cathedral shortly after bells rang out in celebration of the appointment, elementary school teacher Isabel Panez said: "For us Peruvians, it is a source of pride that this is a pope who represents our country."

Read more here.

Image source, Getty Images

Austria's Cardinal Christoph Schönborn has praised the new Pope, saying Robert Prevost has "qualifications that speak for this office".

“Leo XIV was my insider tip.

"A North American who became a bishop in Peru. That showed how well he empathised and fit in with people living there," Schönborn tells the Austrian Broadcasting Corporation, ORF TV.

He notes that that's why the late Pope Francis "brought [Prevost] to Rome", as Francis "thought he would be good," he says.

The former Archbishop of Vienna, who is over 80, was not eligible to take part in the papal vote.

However, he was surprised that Prevost was voted in so quickly. "There must have been strong traction in Conclave that he was the one, otherwise you don’t make it in just four [rounds of] votes," he says.

There is a lot of symbolism behind each item of clothing that the Pope wore when he first greeted worshippers from the Vatican balcony.

Here is a breakdown of what these items mean:

• Zucchetto: A small skullcap worn by clerics of Catholic Churches. The colour of it indicates the rank of a clergy member. For example, red zucchettos are worn by cardinals, while a white zucchetto - as seen in the photo above - is worn only by the Pope.
• Mozzetta: A short, elbow-length cape worn over the shoulders by clergy in the Catholic Church. Like the zucchetto, its colour and style signify rank. Red silk or velvet is reserved for the Pope.
• Surplice: A loose-fitting, white garment that is traditionally worn during liturgical services, symbolising purity, humility and service.
• Cross on gold cord: A pectoral cross is worn by bishops, cardinals and the Pope. But the Pope's is traditionally attached to a gold cord as a sign of humility, compared to a more ornate chain.
• Stole: A long, narrow strip of cloth that is often richly decorated and that symbolises authority and responsibility.
• Fisherman's ring: A gold signet ring that is part of the Pope's official regalia. It features an image of St Peter fishing from a boat, as well as the Pope's name inscribed around the image. The ring is meant to link the Pope directly to St Peter.

Image source, Reuters

More congratulations are coming in from leaders in the Philippines, Asia's most Catholic country.

Echoing other world leaders, President Ferdinand Marcos Jr says he hopes Leo XIV will "continue to bring the Church closer to the poor and disadvantaged".

"The Filipino people are also praying for the new Pope's strength and good health as he leads the faithful with grace, wisdom and compassion.

"May his life and ministry inspire us to persevere in our daily walk with our Lord Jesus Christ," he wrote in a statement.

The new Pope's call for peace and compassion for the vulnerable "resonates deeply with the Filipino faithful", says Speaker of the House Ferdinand Martin G. Romualdez, urging the country to unite in prayers for the new pontiff.

“The challenges before the world are great, but so too is the light that now shines from Rome. May Pope Leo XIV guide us toward peace, healing and renewed faith,” he said.

Tessa Wong
Live Editor

Good morning to our readers in the UK and Europe who have just joined us, and welcome back to our coverage. Here's a quick round-up of what you have missed:

• Leaders from across the globe have been quick to offer their well wishes to Pope Leo XIV
• US President Donald Trump and Vice-President JD Vance - who converted to Catholicism in 2019 - have congratulated the new pope, with Trump saying it was a "great honour" to see the first North American pontiff
• In the US, Catholics are continuing to react with enthusiasm and joy
• From the Philippines, which has the third-largest Catholic population in the world, to South Korea and Indonesia, Catholics across Asia are celebrating the election
• Australia's PM Anthony Albanese has invited the new pontiff to visit his country which will be hosting a major Catholic conference in 2028
• In Peru, where the new pope did much of his work, many are proud of his election - but allegations of a cover-up of sexual abuse cases will be among the challenges he faces, says our correspondent

The Pope will lead a Mass in the Sistine Chapel at 11:00 local time (10:00 BST), where he'll be joined by cardinals. Stay with us as we bring you more reaction and developments.