Following the passing of Prince Philip on Friday morning, the Royal Family has entered a period of mourning, along with the rest of the United Kingdom.
This will last for the nation until 8am on the day of the Duke of Edinburgh's funeral, which Buckingham Palace has announced will be held at 3pm on Saturday 17 April.
However, royal mourning – also known as court mourning – will continue for several extra days, and end on Thursday 22 April.
In line with tradition, as a mark of respect to the Queen's late husband, members and representatives of the Royal Household will alter how they dress during this time.
According to The Telegraph, royal family members will be expected to wear black or dark clothes throughout this period – and a black armband if they are wearing military uniform.
Their appearance will likely be similar to the sombre clothing they usually don during the annual Remembrance events each November.
Additionally, the household will use black-edged stationary for all written communications made in relation to the duke's death.
For the next two weeks, neither the Queen nor other members of the family will carry out any official duties.
Indeed, Prince William has already withdrawn from this weekend's BAFTA Awards due to his grandfather's passing.
The royals aren't the only people required to alter their wardrobes – presenters and newsreaders have also been instructed to wear black or dark clothes as well as black ties, while it is recommended MPs wear black armbands during work time.
The duke, who died aged 99 at Windsor Castle, will be given a ceremonial royal funeral at St George's Chapel in Windsor.
It has been announced that Prince Harry will be travelling from his home in California to attend, while his heavily-pregnant wife Meghan Markle has been recommended by doctors not to fly.
On Saturday, the duke's coffin will be transported in a modified Land Rover that he helped design.
Watch: The wonderful life of Prince Philip, The Duke of Edinburgh