Britain's King Charles III's planned state visit to the Vatican in early April will go ahead despite Pope Francis's hospitalisation for pneumonia, Buckingham Palace said on Tuesday.

Charles, who is the head of the Church of England, is scheduled to meet his Catholic counterpart on 8 April, according to the palace's program. A Buckingham Palace source expressed "our hopes and prayers that Pope Francis's health will enable the visit to go ahead."

The king wrote to Francis when the 88-year-old pontiff was struck down with pneumonia in both lungs, for which he has been receiving treatment in Rome's Gemelli hospital for more than a month, the source added.

Charles is set to be accompanied by his second wife Camilla on his 7 to10 April visit to the Holy See and Italy, his first to both as king.

After his Vatican visit, Charles will meet Italy's Prime Minister Giorgia Meloni and President Sergio Mattarella. 

He is set to become the first British monarch to address a sitting of the Italian parliament, according to Buckingham Palace.

His last visit to the Holy See was in 2019, when he likewise met Pope Francis.

After revealing in February 2024 that he was being treated for cancer, the 76-year-old sovereign has since October resumed his trips abroad.

The Church of England split from the Roman Catholic Church in the 16th century, after Pope Clement VII refused King Henry VIII's request to annul his first marriage to Catherine of Aragon.

In response Henry launched the English Reformation, making himself supreme leader of the country's Church and steering it towards Protestantism.