On 3 April 2018, Philip was admitted to King Edward VII's Hospital for a planned hip replacement, which took place the next day. This came after the Duke missed the annual Maundy and Easter Sunday services. On 12 April, his daughter, Princess Anne, spent about 50 minutes in the hospital and afterward said her father was "on good form". He was discharged the following day.
On 20 April 2018, Ardern attended the Commonwealth Heads of Government Meeting 2018 in London, where she was selected to deliver a toast to the Commonwealth at a state banquet of world leaders. She also had her first private audience with Queen Elizabeth II.