The Queen and members of the royal family are to wear mourning bands when they carry out public engagements in honour of the late Prince Philip.
Once the death was confirmed, members and representatives of the royal family would have been expected to wear black or dark colours and mourning bands - in line with tradition.
READ: Princess Anne reveals 'life will be completely different' without father Prince Philip
WATCH: Prince Philip dies aged 99
Members of Parliament will also no doubt wear black armbands on their left arm as part of the mourning period.
MORE: Prince Philip obituary: The Duke's incredible life from childhood to duty
READ: First details for Prince Philip's funeral announced
Although this is a time of sorrow, social engagements will be cancelled, however, certain official engagements may still go ahead for some royals.
The funeral, which is taking place on Saturday 17 April, will be held at St George's Chapel in Windsor Castle. In line with his own wishes, the Duke of Edinburgh will be given a ceremonial royal funeral - the same honour given to the last three sovereign's consorts, including the Queen Mother in 2002.
Prince Philip died aged 99 on Friday
Diana, Princess of Wales was also given a form of ceremonial royal funeral despite no longer having the title of Her Royal Highness.
In compliance with coronavirus restrictions, there will be no public access and no procession will take place within the grounds of the castle.
MORE: The Duke's incredible life from his years of service to his childhood
SEE: Prince Philip's sweetest family pictures with his children and grandchildren
The funeral will be broadcast on the BBC, and there will be a minute's silence held. The occasion will celebrate Philip's life and service. There will also be a national mourning period until Saturday, while the royal family will have two weeks of mourning.
Buckingham Palace said Prince Philip died at Windsor Castle on Friday, two months before his 100th birthday, leaving the Queen and the royal family "mourning his loss".
Prince Charles and Prince Philip wearing black bands at the Queen Mother's funeral
Saluting batteries began firing 41 rounds at one round every minute from midday on Saturday in cities including London, Edinburgh, Cardiff and Belfast, as well from Royal Navy warships.
Philip, famously described by the Queen as her "constant strength and guide", was known to have wanted a minimum of fuss at his funeral.
Buckingham Palace said: "During the coronavirus pandemic, and in light of current Government advice and social distancing guidelines, modified funeral and ceremonial arrangements for His Royal Highness the Duke of Edinburgh are being considered by Her Majesty The Queen."
The final guest list for the funeral will be confirmed in the couple of days ahead of Saturday's funeral.
Make sure you never miss a ROYAL story! Sign up to our newsletter to get all of our celebrity, royal and lifestyle news delivered directly to your inbox.