Guests and officials take their seats inside Westminster Abbey in London, for the State Funeral Service for Queen Elizabeth II. Photo: AFP / Pool
The funeral service to remember Britain's longest-reigning monarch, Queen Elizabeth II, has begun at Westminster Abbey.
Among the guests are world leaders including US President Biden and hundreds of other foreign dignitaries.
Around 200 people recognised in the Queen's birthday honours are also there.
King Charles III led a sombre procession behind his mother's coffin from Westminster Hall to the abbey.
The Queen's coffin was conveyed - in the first of three processions throughout the day - through Parliament Square, a distance of about 250m.
The Prince of Wales and the Duke of Sussex walked side-by-side behind their father, the King, who walked alongside his siblings, the Queen's four children.
The procession from the abbey saw the State Gun Carriage carry the coffin, drawn by 142 sailors. A guard of honour stood in the square made up of all three military services.
As they walked to the abbey the royals were accompanied by the Massed Pipes and Drums of Scottish and Irish Regiments, the Brigade of Gurkhas, and the Royal Air Force and the tolling of the abbey bell.
US President Joe Biden, French President Emmanuel Macron and Canadian Prime Minister are among the world leaders who have arrived at the abbey, while six former British prime ministers are also present.
Some 2000 mourners are bidding farewell to the Queen at the state funeral, including 500 dignitaries - with presidents, prime ministers and foreign royalty among the guests.
There are also members of many European royal families, including Belgium, the Netherlands, Spain and Denmark, as well as the Emperor and Empress of Japan.
Former prime ministers Theresa May, Tony Blair, David Cameron, Gordon Brown, John Major and Boris Johnson are at the historic abbey ahead of the ceremony.
New Zealand Prime Minister Jacinda Ardern on her way to the funeral of Queen Elizabeth II. Photo: RNZ / Corin Dann
About 200 people who were recognised in the Queen's birthday honours also received invitations.
Knife crime campaigner Natalie Queiroz told BBC Breakfast she was "totally speechless" when she was asked to attend.
"I think it reflects Her Majesty because she wanted to constantly be in touch with her people and even on her final moments she's made sure that her people are here represented."
Barbara Crellin, a volunteer emergency responder, said she "just cried and cried" when she was invited and described herself as "so humbled and privileged to be here".
Crowds gathering in Hyde Park to watch the Queen's funeral on a big screen. Photo: RNZ / Corin Dann
As London prepares for as many as one million visitors for the historic occasion, roads and bridges are closed to traffic and an unprecedented security operation is under way.
All public viewing areas for the procession are already full, London's City Hall said.
Millions of people will be watching the funeral across the country and most workplaces are closed for a bank holiday.
The event is also expected to be watched by millions around the world, with the Queen the head of state for 14 realms throughout the Commonwealth.
For those not invited big screens have been put up in cities across the country, while some cinemas, pubs and other venues are also showing the once-in-a-generation event.
The final people to attend the Queen's lying-in-state paid their respects at Westminster Hall just after 6.30am local time - after four-and-a-half days and a queue which stretched as far as Southwark Park in south-east London.
This is the first state funeral to be held since Sir Winston Churchill's in 1965.
The service is being conducted by the Dean of Westminster David Hoyle, with the Archbishop of Canterbury Justin Welby giving the sermon.
The Order of Service shows a service filled with traditional church music and readings from the Bible.
Towards the end the Last Post will be played before there will be a two-minute national silence.
Following the service, the coffin will be drawn in a walking procession from the Abbey to Wellington Arch, at London's Hyde Park Corner, to the sombre toll of Big Ben.
Gun salutes will also fire every minute from Hyde Park during the procession and people can watch in person from designated viewing areas along the route.
Once at Wellington Arch, at about 1pm, the coffin will be transferred to the new State Hearse for its final journey to Windsor Castle. There, the Queen's coffin will enter St George's Chapel for a committal service.
Attended by a smaller congregation of about 800 guests, the committal service will be conducted by Dean of Windsor David Conner, with a blessing from the Archbishop of Canterbury.
At a private family service later, the Queen will be buried alongside her late husband, the Duke of Edinburgh, at the King George VI memorial chapel, located inside St George's Chapel.
- BBC