On Wednesday, King Charles, Queen Camilla and Prince William joined tens of thousands at Southsea Common in Portsmouth to mark the 80th anniversary of D-Day.

King Charles, who led a moving tribute to the fallen at the national commemoration, had been determined to attend the service while undergoing cancer treatment. Prince William also delivered a speech to veterans and members of the public who had gathered for the occasion.

While Charles will not attend all of the engagements planned for the two-day tribute in the UK, he was determined to attend Wednesday’s service after being given the go-ahead by his medical team. “There are some key dates the king has been determined not to miss. One is Trooping the Colour and another is the D-Day commemorations which are very important to both the king and the queen,” an insider told Vanity Fair.

The royals, who will attend several engagements alongside thousands of veterans and members of the public, appeared visibly moved by Wednesday’s commemorative service. At one point Queen Camilla had tears in her eyes as she heard veteran Eric Bateman recount how he lost his best friend on the battlefield eight decades ago.

King Charles delivered his first speech since his cancer diagnosis and was joined on stage by Queen Camilla. There was a standing ovation for the monarch who told the nation to “cherish and honor” those who served that day and to “live up to the freedom they died for.” He said: “The stories of courage, resilience and solidarity which you have heard today and throughout our lives cannot fail to move us, to inspire us and to remind us of what we owe to that great wartime generation, now tragically dwindling to so few.”

“It is our privilege to hear that testimony, but our role is not purely passive. It is our duty to ensure that we and future generations do not forget their service and their sacrifice in replacing tyranny with freedom.”

Prince William also addressed the audience and read an excerpt from the diary of Captain Alastair Bannerman, a soldier who was part of D-Day, addressed to his wife on the morning of the landings. William told the flag-waving crowd he was “deeply honored” to be part of proceedings on Southsea Common and said “We will always remember those who served.”

Events to commemorate D-Day are taking place Wednesday and Thursday in the UK and France to remember the fallen.

The service hosted by actress Dame Helen Mirren also featured first-person accounts from D-Day veterans, war-time songs and music from the Royal Drummers. Prime Minister Rishi Sunak also read an address which was delivered to the troops ahead of the D-Day landings.

The show which included a Flypast, concluded with a gun salute from the frigate HMS St Albans, which sailed past in the Solent, and a rendition of the national anthem before a flypast by the Red Arrows and Typhoon jets.

Meanwhile Anne, Princess Royal, the Colonel-in-Chief of The Royal Regina Rifles, was in Normandy to unveil a statue and inspect military troops.

While King Charles’s schedule includes time to rest and recuperate as he undergoes treatment, Prince William will have a significant profile in the coming days. As well as attending a Canadian ceremony at Juno Beach Centre at Courseulles-sur-Mer, France, the Prince of Wales will then represent his father at the international commemorative ceremony at Omaha Beach, Saint-Laurent-sur-Mer, on Thursday alongside 25 heads of state and veterans from around the world.