Queen Elizabeth II will on Wednesday attend a Commonwealth luncheon in London following a grand four-day diamond jubilee celebration which was marred by the illness of her husband, Prince Philip.
The queen will host heads of government and representatives of the Commonwealth nations at Marlborough House, but will be without her husband who is recovering from the bladder infection that hospitalised him on Monday.
The couple's youngest son Prince Edward told reporters after visiting Philip in hospital that his father was "getting better" but he will remain in hospital for several days and that the queen was "bearing up but missing him."
The monarch on Tuesday brought the official public celebrations to a close when she greeted 1.5 million cheering subjects from the balcony of Buckingham Palace.
A dramatic flypast capped four days of celebrations marking her 60th year on the throne as the crowd waved Union Jack flags at the monarch and her family, surrounding the palace in a sea of red, white and blue.
The 86-year-old monarch later said in a special television message shown across the nation and the Commonwealth that the jubilee had been a "humbling experience."
"It has touched me deeply to see so many thousands of families, neighbours and friends celebrating together in such a happy atmosphere," the queen said.
"I will continue to treasure and draw inspiration from the countless kindnesses shown to me in this country and throughout the Commonwealth," she added. "Thank you all."
The queen braved the rain with her heir Prince Charles and his wife Camilla as well as Prince Harry, Prince William and his wife Catherine to wave from the balcony.
"We were told by police that there were 1.5 million in and around The Mall area," a spokeswoman for Buckingham Palace told AFP in reference to the packed avenue running from the palace to Trafalgar Square.
The crowd boomed the national anthem as historic World War II planes flew overhead, followed by the Royal Air Force Red Arrows display team who filled the skies with plumes of red white and blue smoke.
The queen's guard also released celebratory cascades of rifle fire.
Minutes earlier, the royals had driven to the palace from the Houses of Parliament in horse-drawn carriages, again cheered by thousands -- many of whom camped out overnight to get a glimpse of the queen.
Military bands and more than 100 mounted soldiers in traditional uniform accompanied the carriages in a classic display of British pageantry. Banners saying "Elizabeth the Great" were held above the crowd.
In Philip's absence, Charles and Camilla joined the queen, who was dressed in a mint-green silk coat scattered with crystals, in the red and gold 1902 state landau.
Prince Harry joined William and Catherine, who wore a beige lace dress by Alexander McQueen, as they smiled and waved from their own carriage -- their first such carriage trip since William and Catherine married in April 2011.
Charles had earlier taken his father's place by the queen's side at a special jubilee service at St Paul's Cathedral attended by political leaders, foreign ambassadors and royals.
Leading the service beneath the imposing dome of the cathedral, Rowan Williams, the Archbishop of Canterbury and leader of the world's Anglicans, paid tribute to Philip as well as the monarch.
"We are marking six decades of living proof that public service is possible and that it is a place where happiness can be found," said Williams, adding that their prayers were with Philip.
US President Barack Obama also paid tribute to the queen on Tuesday, describing her as "tireless leader."
"While many presidents have come and gone, your majesty's reign has endured," he said in a video message. "That makes your majesty both a living witness to the power of our alliance and a chief source of its resilience."
The monarch insisted on attending Monday's spectacular concert in front of the palace -- which featured stars including Paul McCartney, Elton John and Stevie Wonder -- despite Philip's ill health.
After the final set, Prince Charles urged the crowd to show their support, and they responded by chanting "Philip, Philip".
Philip's new health scare comes after he suffered chest pains during the Christmas break and was treated for a blocked coronary artery.
He appeared in good health on Sunday as he travelled on the royal barge in chilly conditions during a 1,000-boat river pageant, the centrepiece of the jubilee, but doctors said it could have worsened his infection.
AFP, photo-The British Monarchy