The phrase "London Bridge is down" was to be used to communicate the death of the Queen to the Prime Minister of the United Kingdom and key personnel, setting the plan into motion.
Funerals and coronations of members of the royal family are typically organised by the Earl Marshal and the officers in the College of Arms.
Initially, codenames were used by key officials in an effort to prevent switchboard operators of Buckingham Palace from learning of the death prior to a public announcement.
[4][5] When King George VI died in 1952, key government officials were informed with the phrase "Hyde Park Corner".
[1] Several codenamed funeral plans for royal family members in the late-20th and early-21st centuries have used the names of prominent bridges in the United Kingdom.
[1][6] As of March 2017[update], the phrase Operation Forth Bridge referred to the death and funeral of Prince Philip, Duke of Edinburgh, who died in 2021.
[9] A 2024 biography of Charles III by Robert Hardman claimed the King's funeral arrangements have "been upgraded to Operation London Bridge, mirroring those of Elizabeth II".
[10] Preparations for Queen Elizabeth II's death and funeral date back to the 1960s, with the plan having undergone multiple changes in the decades since.
The Guardian reported that The Times had 11 days of prepared coverage ready and that ITN and Sky News had long rehearsed her death, substituting the name "Mrs Robinson" for the Queen's.
[3] Ten days after the Queen's death, a state funeral led by the Archbishop of Canterbury would be held at Westminster Abbey.
Were the death of the Queen to occur in Scotland, "Operation Unicorn" called for The Palace of Holyroodhouse, St Giles' Cathedral, and the Scottish Parliament to serve as the focal point of gatherings, with a condolence book open to the public at the latter location.
[3] One day after the Queen's death, the Accession Council would meet at St James's Palace and Charles would be proclaimed king.
[1][20] Parliament would meet that evening when MPs would swear allegiance to Charles III and express condolences for the Queen's death.
[3] On the third day after the Queen's death, Charles III would receive the motion of condolence at Westminster Hall in the morning and then depart for a tour of the United Kingdom.
On the next day, Charles III would visit Northern Ireland, where he would receive a motion of condolence at Hillsborough Castle and attend a service at St Anne's Cathedral, Belfast.
Seven days after the Queen's death, Charles III would visit Wales, receiving a motion of condolence at the Welsh parliament and attending a service at Llandaff Cathedral in Cardiff.
[21] Although the operation was intended to be brought into action on the day that Elizabeth II died (identified in the plan as "D-day"), the late time of her death rendered it inconvenient to convene the accession council at short notice.
[25][26] Police were deployed in key areas in Scotland to maintain security for the royal family and Elizabeth's body as it moved to Edinburgh Airport.
[28] Officials from Buckingham Palace and Clarence House, known as the Inter-Realm Working Group, would brief representatives of the Commonwealth realms about the funeral and succession plans surrounding Operation London Bridge.
[1] These realms had devised their own plans for what happened in their respective countries in the days after Elizabeth II's death, which ran concurrently with Operation London Bridge.
The prime minister and governor-general would then return to Canberra to make their statements before departing for London with the Royal Australian Air Force.
[30] The Australian Defence Force organised several gun salutes coinciding with events in London and participated in ceremonies in the United Kingdom.
[36] After receiving the news about the Queen's death, the governor general would recall the Cabinet to Parliament Hill and proclaim that Canada has a new "lawful and rightful liege".
Flags on all federal buildings and establishments in Canada and abroad would be flown at half-mast from the notification of death until sunset on the day of the funeral or memorial service.
[32] Plans for the Royal Canadian Mounted Police (RCMP) to participate in the funeral procession in London were in place for decades.
[41][42] Once informed, the head of the Ministry for Culture and Heritage had to request the flying of the flag of New Zealand at half-mast on government buildings and other chosen facilities up to the day of the funeral, excluding the date the new sovereign is proclaimed.
[42] A state memorial service would be expected, although decisions on accompanying events, as well as government protocol, would be determined by the prime minister.