The Queen is to carry out her first major public engagement since the death the Duke of Edinburgh, when she attends the State Opening of Parliament later.
Prince Philip spent decades accompanying the monarch to the event.
This year’s ceremony will be pared back because of the pandemic.
It will be the monarch’s first official appearance in public in her role as head of state and her first engagement outside Windsor Castle since the death of her husband on 9 April, aged 99.
However, the Queen, 95, has been continuing her official duties, including taking part in virtual events, since a two-week period of royal mourning ended.
The Prince of Wales and the Duchess of Cornwall will join the Queen for the state opening, during which the monarch marks the beginning of the parliamentary session by delivering the Queen’s Speech, which sets out the government’s legislative plans.
Charles has been at his mother’s side for the last three occasions – in December 2019, October 2019 and Jun 2017 – after his father Philip fell ill with an infection, two months before he retired from public duties.
The event is usually known for its pomp and pageantry but will be scaled back this year because of the pandemic.
The Queen, in day dress and hat, will travel from Buckingham Palace to the Palace of Westminster in a Bentley limousine, rather than by carriage.
MPs and members of the House of Lords will have to wear masks throughout unless they are exempt, and everyone present will have to take a Covid test beforehand and only be allowed to attend if they have a negative result.
No diplomatic or non-parliamentary guests have been invited, with just 108 people attending, rather than up to 600 as is the norm.
Fewer politicians and peers will attend, with only 74 people in the chamber, including the Queen, Prince Charles, Camilla, Speaker Sir Lindsay Hoyle, Prime Minister Boris Johnson and Labour leader Sir Keir Starmer, representatives from the House of Lords and House of Commons and those involved in the ceremonial procession.
There will also be 17 members of the Lords and 17 MPs in the Royal Gallery.
Another amendment is that the Lord Chancellor Robert Buckland will not hand the speech directly to the Queen as is usually the custom, but place it on a table instead.
There will also be no military street liners or lining of the sovereign’s staircase. There will be no military band or Guard of Honour outside the Palace of Westminster or as part of the procession from Buckingham Palace.
However, the ancient tradition of the Black Rod will still take place.
This sees the doors of the Commons shut in the face of Sarah Clarke, Lady Usher of the Black Rod, as she arrives to summon MPs. She then has to strike the door three times before it is opened, symbolising the Commons’ independence from the monarchy.
The Queen will not wear the heavy Imperial State Crown, which will instead be carried on a cushion and placed on a table nearby as it was in 2019.
The monarch last wore the crown, which is made of more than 3,000 gemstones and weighs two pounds and 13 ounces, for the 2016 state opening.