The Queen will celebrate the second day of her Platinum Jubilee today, with the highlight a service of thanksgiving at St Paul's Cathedral attended by senior royals and politicians.
The 96-year-old monarch pulled out of the service last night due to ongoing mobility issues, experiencing "some discomfort" during Thursday's Trooping the Colour and Royal Air Force flypast.
Officials said the journey from Windsor Castle, where she spends most of her time, to London and the activity involved for the service was too much and a regrettable but sensible decision had been taken.
A palace source said it had always been the Queen's hope that she would attend rather than a firm commitment.
She will not be the only absentee. Prince Andrew has tested positive for Covid-19 and will also miss the service, a Buckingham Palace spokesman said on Thursday.
Menawhile, Prince Charles, Camilla and the Duke and Duchess of Cambridge will take part in a procession. Wider members of the family are also expected to be present, including Prince Harry and Meghan followed by a Guildhall reception.
Elsewhere, Princess Anne will see penguins at Edinburgh Zoo as members of the Royal Family visit the nations of the UK to mark the Platinum Jubilee. She will be joined by her husband, Vice Admiral Sir Tim Laurence, on her visit to the Scottish capital
Here's our run-down of today’s main events so you don't miss out...
Follow the Queen's Platinum Jubilee celebrations in our live blog here
11.30am - The National Service of Thanksgiving
The service will include Bible readings, prayers, and hymns to express gratitude for Elizabeth's reign. Over 400 people have been invited to the service - all of whom have been recipients of Honours in the New Year or Birthday Honours lists.
Boris Johnson, who will give a New Testament reading, and members of his Cabinet are among the guests along with Labour leader Sir Keir Starmer, first ministers of the devolved governments and former prime ministers.
The diplomatic world will be represented by high commissioners and ambassadors from across the world and also attending are governors general and clergy from world faiths.
The Archbishop of York Stephen Cottrell will give the sermon after the Archbishop of Canterbury Justin Welby tested positive for Covid-19. The Dean of the Chapel Royal, Dame Sarah Mullally, Bishop of London, will give the Collect and the Blessing, and the Dean of St Paul's will conduct the service.
Young people representing countries where the Queen is head of state will lead the 'Act of Commitment' celebrating the life and reign of the monarch, led by the Reverend Robert Kozak.
The Dean of St Paul's, Dr David Ison, will say: "We come together in this cathedral church today to offer to God our thanks and praise for the reign of her majesty the queen and especially for her seventy years of faithful and dedicated service."
The cathedral's 'Great Paul' bell - the largest in the country and dating back to 1882 - will also be rung for the first time at a royal occasion since being restored last year after a mechanism broke in the 1970s.
The event will feature a new anthem by Judith Weir, Master of the Queen's Music, that sets to music words from the third Chapter of the Book of Proverbs.
Bible readings, hymns and prayers to express thankfulness for the Queen's reign, faith and service will also be heard by the congregation as the nation marks the monarch's 70 years on the throne.
Before the service begins, the Band of Her Majesty's Royal Marines Portsmouth (Royal Band), will play as the congregation arrives and the State Trumpeters of the Household Cavalry will perform to mark royal arrivals, while the Fanfare Trumpeters of the Central Band of the Royal Air Force will accompany later in the service.
The choirs of St Paul's Cathedral and Her Majesty's Chapel Royal will join together to sing the Vivats, I Was Glad by Sir Hubert Parry, performed at every coronation and now for the Queen's Platinum Jubilee.
The monarch is skipping the service on Friday "with great reluctance" and is believed to have experienced episodic mobility issues during Thursday's events.
A statement issued on Thursday evening said: "The Queen greatly enjoyed today's birthday parade and flypast but did experience some discomfort.
"Taking into account the journey and activity required to participate in tomorrow's National Service of Thanksgiving at St Paul's Cathedral, Her Majesty, with great reluctance, has concluded that she will not attend."
12.25pm - Guildhall reception for Royal Family members and the congregation
Following the service, the royal family will attend a Guildhall reception hosted by the Lord Mayor of London and City of London Corporation.
Members of the congregation will also be invited to the event.
Elsewhere in the UK
The Princess Royal will see penguins at Edinburgh Zoo as members of the royal family visit the nations of the UK to celebrate the Queen's Platinum Jubilee.
She will be joined by her husband, Vice Admiral Sir Tim Laurence, on her visit to the Scottish capital on Friday.
Anne will join children for an animal handling session in the Rainforest Room at the zoo, before visiting the penguin enclosure. She will then visit HMS Albion and inspect a Guard of Honour before boarding the ship.
On the flight deck of the amphibious assault vessel the princess will meet members of the ship's company and representatives from charities across Scotland supported by the Queen and Anne as patrons, before cutting a commemorative cake.
CELEBRATE THE JUBILEE ON TV
Friday
9.15am The Queen’s Platinum Jubilee: A Service of Thanksgiving, BBC1
5pm Blue Peter Jubilee Takeover! CBBC
6.45pm The One Show: Jubilee Special, BBC1
7.30pm The Crown Jewels, BBC1
Saturday
12.40am The Epsom Derby, ITV
5pm The National Lottery Jubilee Street Party, ITV
7.30pm Platinum Party at the Palace, BBC1
10.45pm Elizabeth: The Golden Age, ITV
Sunday
12.10pm Songs of Praise: Platinum Jubilee Special, BBC1
1pm The Platinum Pageant, BBC1
8pm Platinum Jubilee: What A Weekend! BBC2