Plans and timeline following the death of Queen Elizabeth II

On her death Charles automatically became King of the United Kingdom and Australia and will be known as King Charles III, while his wife Camilla will be known as Queen Consort.

There have long been plans in place for the passing of the British Monarch.

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These are described in a timeline of days, with the date of death known as D Day, or D+0.

The day that follows is called D+1, and so on.

The plan for the Queen's death is called Operation London Bridge.

Because she died in Scotland, the initial part of the plan before she arrives in London, is known as Operation Unicorn.

Here's what's expected to occur in the United Kingdom and Australia in the coming days.

Buckingham Palace contacts Governor-General David Hurley, advising him of the Queen's death. He then notifies Prime Minister Anthony Albanese and issues a short statement.

Mr Albanese makes a national address, wearing a black tie. Prime ministerial staff may have carried around a black tie in preparation for the Queen's death.

Parliament, which was to sit on Friday until Thursday, September 15, is suspended for 15 days.

All flags are lowered to half-mast.

Condolence books are opened at Parliament House, Government House and on the Prime Minister and Cabinet website.

Guns salute at dusk at Parliament House. There are 96 rounds, one for each year of her life, at 10-second intervals.

The Queen is formally announced as dead on Thursday afternoon.

Prime Minister Liz Truss is understood to be notified of the death at 4.30pm, before a public announcement by Buckingham Palace at 6.30pm.

Ms Truss addresses the UK while wearing black.

The King and Queen Consort remain in Balmoral overnight.

Governor-General David Hurley, Prime Minister Anthony Albanese, Leader of the Opposition Peter Dutton and other government ministers lay wreaths at Queen's Terrace in Parliament House.

There will be an invitation for other members or senators to lay wreaths.

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On Friday morning, it is expected the Queen's body will be transported from Balmoral to Aberdeen, and taken by Royal Train to Edinburgh.

In Edinburgh, the Queen's coffin is expected to lie at medieval palace Holyroodhouse for one day.

Meanwhile in London, the Proclamation of new Sovereign will take place.

The King has already succeeded the Queen, his appointment automatic after her death, but he will be ceremonially presented as the new monarch on Friday morning.

The proceedings will begin at 10am in St James's Palace.

The King is expected to address the public on Friday.

The Executive Council, a small group of key officials including Mr Albanese and Attorney-General Mark Dreyfus, will meet to confirm Australia's next monarch.

The Executive Council is the Australian equivalent of the UK's Privy Council.

Mr Albanese will recommend to the Governor-General that he issue a proclamation of accession, confirming King Charles III as Australia's monarch.

At 12pm, the Governor-General will read the proclamation at Parliament House and there will be a 21-gun salute. This event is open to the public, and once finished states can make their own proclamations.

The Queen's body is expected to travel the St Giles Cathedral, near Edinburgh castle, in procession.

Mourners will gather to Holyroodhouse and St Giles to pay their respects.

The Australian High Commissioner to the UK Lynette Wood will attend a reception with the King.

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The Queen's body will journey to London, arriving at St Pancras.

Operation London Bridge commences.

Mourners will pay respects outside the train as it travels slowly to Buckingham Palace.

The Queen's body will be put in the throne room at Buckingham Palace, before being taken to Westminster Hall.

The body will stay in Westminster Hall for four days.

The Australian High Commissioner will attend the King's Speech to the UK Parliament.

The Prime Minister, his partner Jodie Haydon, the Governor-General and his wife Linda Hurley leave Australia for the UK.

Mr Albanese and Mr Hurley will attend the Lying in the State.

The Queen's coffin will rest on a raised platform in the middle of Westminster Hall.

Each corner of the platform is guarded by units from the Sovereign's Bodyguard, Foot Guards or the Household Cavalry Mounted Regiment.

Members of the public are free to file past the platform and pay their respects.

The King will briefly spend time with the Prime Minister, Governor-General and High Commissioner.

Mr Albanese and Mr Hurley will attend an evening reception with the King, along with other heads of state and international VVIPs (very, very important persons).

The Queen's funeral is expected to be held at 11am in Westminster Abbey. This date is not yet officially confirmed.

Mr Albanese, Mr Hurley and Ms Wood will attend.

At 12.45pm, Ms Wood and her partner will attend a post-funeral reception at Church House.

The Australian delegates will then move to Windsor Castle at 2.45pm.

At 3.45pm Mr Albanese, Mr Hurley and Ms Wood and their partners will attend Committal Service at St Georges Chapel in Windsor.

Queen Elizabeth II will be buried in the King George IV Memorial Chapel.

This day will end the UK's official 10-day mourning period, and also be a public holiday in the UK. However, employers will not be required to give staff the day off.

Flags return to full mast.

The Australian Parliament is able to sit, although the next sitting week dates have not yet been confirmed.

Following the return of the Prime Minister and Governor-General from London (the exact day is still to be confirmed), a national memorial service will be held in Australia, likely in Canberra.

This will be a national day of mourning, and a minute's silence will be held - expected to be at 11am.