William and Kate feel ‘intense anxiety’ at the prospect of becoming King and Queen in the wake of Charles’s cancer diagnosis, Princess Diana’s biographer has revealed

The 75-year-old monarch is undergoing treatment at the same time as the Princess of Wales, leaving William to step in for both his father and wife at public engagements.

Tina Brown, former Vanity Fair editor who also penned the bestselling Diana Chronicles, wrote: “News of Charles’s cancer has put William and Catherine in frightening proximity to ascending the throne… the prospect of it, I am told, is causing them intense anxiety.” Meanwhile, the BBC has said it received complaints from people who believed its coverage of the Princess of Wales’ cancer diagnosis was “excessive and insensitive”.

Kate revealed she was undergoing treatment for cancer in an emotional video message released on March 22, in which she told others battling the disease “you are not alone”. The broadcaster had aired the full video and said it was “mindful” of its reporting approach, and did not speculate on details that had not been made public.

Upon his return this May, Harry could be hoping to make ammends with his estranged brother, who is supporting his wife Kate through her cancer treatment, says royal biographer Richard Fitzwilliams. Fitzwillliams told the Sun: “The Sussexes do spring surprises. This has happened before, and you never know what might happen in the coming weeks or months.

“But I don’t think Harry would do anything without Megan’s consent.” The Duke and Duchess of Edinburgh have celebrated Anglo-French relations at a ceremony marking the 120th anniversary of the Entente Cordiale. Edward and Sophie inspected UK and French troops on Buckingham Palace’s forecourt during the event highlighting ties between the two nations.

The duke and duchess, representing the King who is continuing his cancer treatment and was not at Buckingham Palace, walked past 32 members of the 1st and 2nd Infantry regiments of the Garde Republicaine and then 40 guardsmen from F Company Scots Guards, lined up opposite their French counterparts. French soldiers have guarded Buckingham Palace for the first time marking a historic moment in cross-Channel relations.

France became the first non-commonwealth country to take part in the Changing the Guard ceremony at 11am on Monday, marking the 120th anniversary of the Entente Cordiale. Crowds and members of the royal family looked on as members of the Gendarmerie’s Garde Republicaine joined the Scots Guards to parade together, watched on by crowds.

The French Gendarmerie were marched on and off the palace forecourt by the Band of the Grenadier Guards, who performed both countries’ national anthems as a “symbol of the strength of the relationship between” the two countries. The landmark procession was organised to mark the historic diplomatic agreement between Britain and France that laid the groundwork for their collaboration in both world wars.