King Charles III on Thursday met Pope Leo XIV at the Vatican, marking a historic moment as the British monarch prepares to become the first head of the Church of England to pray publicly with a Pontiff.

Arriving in Rome on Wednesday evening with Queen Camilla, the 76-year-old monarch was received at the Apostolic Palace by a Swiss Guard of honour before a private meeting with Pope Leo in the Papal library. It was Charles’s first encounter with the new Pope, who succeeded the late Pope Francis in May.

At midday, Charles and Camilla are expected to join an ecumenical service in the Sistine Chapel led by Pope Leo and the Archbishop of York, Stephen Cottrell — the most senior cleric of the Church of England. The event, broadcast live by Vatican media, marks the first time in 500 years that a reigning British monarch has prayed publicly with a pope.

The schism between the English crown and the Vatican dates back to King Henry VIII’s break with Rome in the 16th century, after the pope refused to annul his marriage; a decision that created the Church of England.

Thursday’s joint service will focus on conservation and protecting the environment, one of Charles’s long-standing causes. It will feature choirs from both the Sistine Chapel and St George’s Chapel, Windsor Castle.

The royal visit comes amid renewed controversy surrounding Prince Andrew, who recently gave up his Duke of York title after continued scrutiny over his ties to the late US financier Jeffrey Epstein.

Relations between the Catholic and Anglican churches have gradually improved over the past century. Queen Elizabeth II became the first British monarch to visit the Vatican since the split in 1961, and in 2013, UK law was amended to allow royals to marry Catholics without forfeiting their claim to the throne though the monarch must remain Protestant.

“The rapprochement is important because Anglicanism was born in reaction to the Catholic Church,” said Father Hyacinthe Destivelle of the Vatican’s department for promoting Christian unity.

King Charles and Queen Camilla are also expected to attend a service at the Basilica of Saint Paul Outside the Walls, where the king will be made a “Royal Confrater” and presented with a seat reserved for future monarchs.

Charles has visited the Vatican several times and last met Pope Francis in April, shortly before the late pontiff’s passing. The king sent his son, Prince William, to the funeral and his brother, Prince Edward, to Pope Leo’s inauguration mass.

The visit coincides with the Catholic Church’s Jubilee Year, a major event held every 25 years that has drawn millions of pilgrims to Rome.