Prime Minister Liz Truss will join King Charles as he leads "services of reflection" around the United Kingdom, Downing Street has announced.
She is set to travel to Scotland on Monday, followed by visits to Northern Ireland on Tuesday and Wales on Friday as the new monarch goes on a tour of the country.
"The Prime Minister believes it is important to be present for what will be a significant moment of national mourning around the United Kingdom," her official spokesman said.