King Charles, Queen Camilla and the Prince of Wales are due to travel to France on 6 June in order to mark the 80th anniversary of D-Day landings during World War II.
The King and Queen are due to join the Ministry of Defence and Royal British Legion's commemorative event at the British Normandy Memorial at Ver-sur-Mer. Meanwhile, William is due to mark the poignant anniversary alongside the Canadian government at Juno Beach Centre. He will be joined by Canadian armed forces personnel and World War II veterans.
The father-of-three is also expected to attend the international commemorative ceremony at Omaha Beach. William will be joined by veterans and 25 world heads of state.
Ahead of their international outing, the royals are set to attend a commemorative event in the UK, which will be hosted in Portsmouth on 5 June. Other royals will be attending separate events during the course of the two days.
The trio are not expected to be joined by William's wife, the Princess of Wales, who is currently recovering from cancer.
The Prince of Wales' first overseas trip
The trip will mark William's first overseas visit since his wife's diagnosis, and the first overseas visit for the King since he was also diagnosed with cancer earlier in the year.
In recent weeks, Charles has been seen making more public appearances, including a visit to a cancer treatment centre, and the hosting of two garden parties, one of which clashed with an event hosted by the monarch's son, Prince Harry.
Sources stressed that despite the royal's more public role, the King still has cancer and will continue to be treated for the undisclosed form of the disease.
During a visit to Wiltshire this week, the monarch spoke to army veteran Aaron Mapplebeck, about his recovery as they spoke about their treatment.
The veteran told King Charles that he underwent chemotherapy last year for testicular cancer and lost his sense of taste, to which the King replied the same had happened to him, according to The Metro.
Camilla also made a cheeky comment about the King's recovery during a solo outing on Thursday. When asked about her husband, she said he was "doing better" before joking: "Well, he would be if he behaved himself."
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