Numbers will also be strictly limited to only the head of state, or their designated representative, and their significant other.
It’s all part of what is shaping up to be the UK’s biggest police operation in history and the first funeral of a ruling monarch in Britain since that of King George VI in February, 1952.
Even arriving in the UK could be a process bereft of the traditional privacy accorded to world leaders, with British authorities advising governments around the globe to use commercial jets.
Heathrow Airport in London will be off-limits to private flights, while the amount of air traffic coming in has also seen a ban imposed on helicopter transport while in the country.
US President Joe Biden, who officially accepted his invitation to the funeral this morning, is unlikely to cede the security and privacy offered by the traditional presidential transport of Air Force One.
However, in that case, he will have to land at an airfield away from Heathrow and travel from there.