As Queen Elizabeth II's coffin left Buckingham Palace in London for the last time on Wednesday, the new heir to the British throne, William - Prince of Wales, walked side by side with his younger brother, Prince Harry - the Duke of Sussex, in a deliberate show of symbolic unity following a reported rift between the royal siblings.

It marked the second time the duo has come together in the wake of their grandmother's death on Thursday, previously seen on a walkabout at Windsor Castle to view the floral tributes and greet crowds with their spouses over the weekend.

The foursome was united again inside Westminster Hall, where Kate - the Princess of Wales and Meghan Markle - the Duchess of Sussex joined William and Harry respectively in a procession for the short service marking the Queen's Lying-in-State ceremony.

It was in contrast to when the two princes were separated in procession behind their grandfather, Prince Philip's coffin at Windsor Castle in April last year. The duo walking alongside each other will be seen as a message of unity from a grieving royal family. A unifying and healing note was struck when King Charles III lovingly referred to his younger son Harry and daughter-in-law Meghan in his first televised address to the nation last week. It was reciprocated by Harry in his own message in memory of his grandmother as he wished his father well as the new monarch.

There have been reports of a rift between father and son and the two brothers ever since Harry and Meghan announced their decision to step back as frontline royals a few years ago and relocate to the US, where they are now based in California with their two children - Archie and Lilibet, named after the late Queen.

As young schoolboys, William and Harry famously walked in the funeral procession of their mother Diana, Princess of Wales, after she was killed in a car crash in Paris in 1997. At the time, they were joined by their father, then Charles - Prince of Wales.

On Wednesday, King Charles III was accompanied in the procession by William, 40, and Harry, 37, as well as his three younger siblings - Princess Anne, Prince Andrew and Prince Edward.

The Bearer Party of the coffin was formed of the Queen's Company 1st Battalion Grenadier Guards, with an Escort Party of two Officers and 32 Rank and File formed by the 1st Battalion Grenadier Guards.

The 10 Pall Bearers were made up of the Service Equerries to the Queen, both serving and former, and minute guns were fired from Hyde Park by the King's Troop Royal Horse Artillery as the coffin moved in procession to the Palace of Westminster, where it will now rest at Westminster Hall until Monday's funeral.