Britain's Queen Elizabeth II has given a speech to officially mark a new session of the UK parliament.

As is tradition, the speech is written by the government - setting out its priorities - but is read by Queen Elizabeth II.

What is it all about?

The Queen's Speech is a speech read out in the House of Lords chamber to mark the state opening of parliament.

It sets out the programme of legislation that the government intends to pursue in the next parliamentary session.

It marks the formal start of the parliamentary year.

The speech looks at proposed policies and legislation.

It is the only regular occasion when the three constituent parts of the British parliament - the monarch, the House of Lords and the House of Commons - meet.

The Speech is not drafted by The Queen, but by the Government, outlining policies and proposed future legislation. The speech is carried by the Lord Chancellor in a special silk bag and presented to Her Majesty. #QueensSpeech #StateOpeningofParliament pic.twitter.com/X5CpUuwnrV

— The Royal Family (@RoyalFamily) October 14, 2019

When is it?

A state opening happens on the first day of a new parliamentary session - or else shortly after a general election.

This is the 65th occasion on which the queen has opened parliament - every year of her reign except 1959 and 1963, while she was pregnant.

What happens?

State opening is the main ceremonial event of the parliamentary calendar - attracting large crowds and a significant audience.

It begins with Queen Elizabeth II being taken from Buckingham Palace to Westminster by horse and carriage.

She then uses a special entrance the  and goes to the robing room.

Wearing the robe of state - and usually the imperial state crown - she leads a procession through the gallery, packed with 600 guests, to the chamber of the House of Lords.

Britain's Queen Elizabeth II travels in a carriage to the UK parliament for the official state opening in London | Image: Alberto Pezzali/AP/Press Association Images

A House of Lords official known as 'Black Rod' is sent to summon the House of Commons.

The doors to the Commons chamber are shut in his or her face: a practice dating back to the English civil war, symbolising the Commons' independence from the monarchy.

Black Rod then strikes the door three times before it is opened.

Members of the House of Commons then follow Black Rod and the Commons Speaker to the House of Lords - standing at the opposite end to the throne.

The speech is delivered by the Queen from the throne in the House of Lords.

Britain's Queen Elizabeth II delivers the Queen's Speech the state opening of the UK parliament in the House of Lords, London | Image: Toby Melville/PA Wire/PA Images

Then what?

When the Queen leaves, a new parliamentary session starts and parliament gets back to work.

Members of both houses debate the content of the speech and agree an 'Address in Reply to Her Majesty's Gracious Speech'.

Each house continues the debate over the planned legislative programme for several days, looking at different subject areas.

The speech is then voted on by the House of Commons, but rarely in the House of Lords.

Traditions surrounding State Opening and the delivery of a speech by the British monarch can be traced back as far as the 16th century.

The current ceremony dates from the opening of the re-built Palace of Westminster in 1852 after a fire in 1834.