One million poppies have been dropped on thousands of people gathered in the Mall for Commemoration Day, marking 60 years since the end of World War II.
Part of a flypast of World War II aircraft, the poppies were released by a Lancaster Bomber over The Mall as the Queen and Royal Family looked on.
The Queen earlier addressed the crowd, speaking of the "present difficult days for London" after Thursday's bombings.
She said the people of the war generation had set an example.
A Lancaster bomber dropped 1m poppies over the crowds in a flypast
In her address, she told those gathered in Horse Guard's Parade that the years of war had not been in vain - but sadly, it could not be claimed the world had been free from conflict or terror since 1945.
"It does not surprise me that during the present difficult days for London, people turn to the example set by that generation, of resilience, humour, sustained courage, often under conditions of great deprivation," she said.
"That example, and those memories, should be kept alive by younger generations as they in turn strive to keep the peace in our troubled world."
The Queen was later joined by members of the Royal Family, including the Duke of Edinburgh, Prince of Wales, Duchess of Cornwall and Prince Harry, on the balcony of Buckingham Palace, to watch the flypast.
An estimated 250,000 people crammed into The Mall - outside the palace - to witness the spectacle, which also included B25 bombers, Spitfire and Hurricane fighters.
ORDER OF EVENTS
1100 Service of Remembrance and Commemoration at Westminster Abbey
1230 Veterans' lunch at Buckingham Palace
1449 Queen begins parade along The Mall in carriage
1458 Two-minute silence
1500 Queen arrives on Horse Guards Parade for Reflections of WW2 Commemoration Show
1548 Two-minute silence
1558 RAF formation fly past, Queen speaks
1615 Queen leads procession of veterans' organisations' standards
1700 Fly past of WWII aircraft over The Mall
1712 One million poppies released from Lancaster Bomber
The government decided to hold the national commemorations on Sunday - rather than on VE Day or VJ Day - after consulting veterans groups.
The day falls on a symbolic rather than a historically significant date, with the focus on remembrance and thanksgiving.
Earlier in the day, a service at Westminster Abbey was addressed by the Archbishop of Canterbury, Dr Rowan Williams.
Dr Williams described it as a "fitting response" to the bombings on Thursday, in which at least 50 people died.
The Queen laid a wreath in the Abbey before the service
He said: "Today of all days, we need no reminder that the spirit of murder and humiliation is still abroad, as your majesty reminded us on Friday, there is a generation of people for whom the sight of a devastated, bombed London will bring back harsh memories; memories not only of physical damage but of the sense of obligation to go on resisting the venomous tyranny responsible for it."
Members of the Royal Family, including the Queen and the Duke of Edinburgh, the Duke of York, the Earl and Countess of Wessex, the Duke and Duchess of Gloucester, the Duke of Kent and Princess Alexandra, were in attendance.
Prime Minister Tony Blair, Conservative Leader Michael Howard and Liberal Democrat Leader Charles Kennedy were also at the service, alongside hundreds of veterans.
In New Zealand, Prince William laid a wreath in memory of those who died.