Prince William and Harry look sombre as they put on a united front behind the Queen's coffin

Prince William and Prince Harry looked sombre as they marched through the streets of London today (14 September) in a procession moving the Queen's coffin from Buckingham Palace to Westminster.

The brothers joined their father, King Charles III, in walking behind the coffin as it was moved to prepare for the Queen to lie in state, which begins at Westminster today.

Her coffin was pulled by two horses and draped in the Royal Standard flag, with the Imperial State Crown sitting on top of it on a velvet cushion.

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Princes William and Harry were joined by Princess Anne, Prince Andrew, and Prince Edward in the procession, with Prince William dressed in military uniform while Prince Harry wore black, with medals on display on his chest.

After leaving Buckingham Palace, the coffin proceeded down the mall and past the Cenotaph in London, with Big Ben tolling and guns being fired in Hyde Park to mark each minute of the march.

The coffin has now arrived at the Palace of Westminster, where the bearer party carried it to a wooden platform in the oldest part of the estate, Westminster Hall.

William and Harry are among the members of the Royal Family who joined the Queen's coffin in the hall for a short service conducted by the Archbishop of Canterbury, which is expected to last 20 minutes.

The lying in state will then begin, lasting for four days before the Queen's funeral on 19 September. Members of the public will be able to visit the Queen's coffin to pay their respects during this period.

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Both Prince William and Harry released statements in tribute to the Queen following her death on 8 September, with Harry describing the 96-year-old monarch as the 'guiding compass she was to so many in her commitment to service and duty'.

"She was globally admired and respected. Her unwavering grace and dignity remained true throughout her life and now her everlasting legacy," he continued.

William remembered the Queen as 'an extraordinary leader, whose commitment to the country, the Realms and the Commonwealth was absolute', but added that he has 'lost a grandmother'.

The prince added: "While I will grieve her loss, I also feel incredibly grateful. I have had the benefit of The Queen's wisdom and reassurance into my fifth decade. My wife has had twenty years of her guidance and support. My three children have got to spend holidays with her and create memories that will last their whole lives."