The Princess of Wales is to carry out her first major engagement since her operation when she reviews Trooping the Colour, according to the Army’s official website.

Tickets are being sold on the site for the military spectacle which will take place on June 8, the weekend before the main Trooping the Colour ceremony – which is normally reviewed by the monarch.

The website names the King as attending the main Trooping ceremony – also known as the Birthday Parade, as it marks the sovereign’s official anniversary – with bookings now being taken for a ballot for tickets.

But the announcement has caused confusion as there has been no official confirmation from Kensington Palace or Buckingham Palace.

Charles is receiving treatment for cancer and Kate is recovering from abdominal surgery, but it is understood planning for major royal events continues, with organisers remaining flexible in the event of possible changes.

The princess has been spotted being driven close to her home in Windsor following huge speculation on social media about the state of her health.

A screengrab from the Trooping The Colour ticket website on Tuesday night
A screengrab from the Trooping the Colour ticket website on Tuesday night (PA)

It appears the Ministry of Defence hopes Kate, who is Colonel of the Irish Guards, will be well enough to attend one of the key ceremonial events in the armed forces’ year.

But only Kensington Palace, Kate’s official office, can announce her attendance at a royal event and confirmation is not expected until nearer the time.

The Army states on its website: “Trooping the Colour reviewed by Her Royal Highness The Princess of Wales is identical to Trooping the Colour reviewed by His Majesty The King, with the exception that some additional mounted officers ride when His Majesty The King is present.

“Taking part will be over 1,400 soldiers of the Household Division and The King’s Troop Royal Horse Artillery, including 400 musicians from the Massed Bands, all of whom will parade on Horse Guards for the second of two formal Reviews.”

Prince William passing out at Sandhurst
Kate with her mother, Carole Middleton (Tim Ockenden/PA)

Kate left hospital on January 29 and is recuperating at her Adelaide Cottage home close to Windsor Castle after undergoing abdominal surgery but is not expected to return to official duties until after Easter.

An image circulating online shows the princess, wearing sunglasses, sitting in the front seat of a car being driven by her mother, Carole Middleton.

Since his diagnosis, the King has postponed all public-facing duties but is continuing with behind-the-scenes work on his red boxes of state papers and some in-person meetings.

Charles was pictured earlier during a pre-Budget audience with Chancellor Jeremy Hunt at Buckingham Palace, ahead of the politician’s major financial statement on Wednesday.