The Royal Family have arrived at Balmoral including Prince Charles, Prince William and Prince Harry amid concerns for the Queen's health.

Buckingham Place said on Thursday, “Following further evaluation this morning, the Queen’s doctors are concerned for Her Majesty’s health and have recommended she remain under medical supervision. The Queen remains comfortable and at Balmoral.”

The concerning news has sparked fears for the Queen's health with many asking what happens next, if the worst happens. 

Plans have been in place for decades outlining how the public are notified and what happens next, known as Operation London Bridge.

Here is a full breakdown of what Operation London Bridge entails.

What is Operation London Bridge?

As is the case whenever a member of the Royal Family dies, there are strict plans in place for what happens next, none more important than the death of the Head of State.

Each member of the Royal Family has their own code name, detailing the plans in place in the event of their death.

In the Queen’s case, the codename is Operation London Bridge.

Operation London Bridge

In September last year, new details of Operation London Bridge were leaked suggesting the day the Queen dies will be known as D-Day.

UK Government departments will be told to have flags at half-mast within 10 minutes after government officials are told and instructed to show “discretion”.

Prince Charles will become King when his mother passes and will address the nation on the day of his mother’s death.

The Prime Minister will be the first government official to release an official statement.

The Queen will be buried 10 days after her death with Prince Charles expected to embark on a UK tour in the days leading to the burial.

According to Politico, Parliamentary business will be suspended for 10 days and the sovereign’s coffin will lie in state for three days at the Houses of Parliament.

The Royal household will issue an official statement notifying the nation of the monarch’s passing.

What happens when the Queen dies?

On the day of the monarch’s death, Ministers will receive a call and an email reading: “Dear colleagues, It is with sadness that I write to inform you of the death of Her Majesty The Queen.”

The details of the funeral will be announced while government and royal websites will display a black banner.

Charles will deliver a speech to the nation before meeting the Prime Minister.

The day after the Queen’s death government officials will proclaim Charles their new king.

The Queen’s funeral arrangements

The day of the funeral will be a day of national mourning although employers will not be forced to give employees the day off work.

The funeral will be held at Westminster Abbey and a national two-minute silence will be held at noon.

The Queen will be buried at King George VI Memorial Chapel.