Prime Minister David Cameron will join his staff and guests today for a party in Downing Street to mark the Queen's Diamond Jubilee.
The event is part of the Big Jubilee Lunch - which will see thousands of neighbourly meals being staged across the country in honour of the Queen's 60-year reign.
The street outside the official London home of past prime ministers will also host charities, who have a royal patron or are supporters of the Lunch.
Local branches of the Scout Association, Girlguiding UK, Age UK and Contact the Elderly will join the staff from Downing street, and the party atmosphere will be created with games, music and face painting.
Larry, the Downing Street resident cat, plays with bunting in No 10's garden as the street prepares for the Diamond Jubilee
The Duchess of Cornwall is patron of the event, led by the Eden Project, which aims to encourage neighbourhoods to come together to share lunch and a few hours of community, friendship and fun.
This year people across all 54 Commonwealth countries are being encouraged to hold their own Big Jubilee Lunch events as part of the celebrations.
Almost six million Britons plan to throw a house party this weekend for the Diamond Jubilee, a study has suggested.
Some 12% of people plan to hold celebrations at home to mark the Queen's 60-year reign, spending £83 each on average, amounting to £424 million spent across the country on food, drink and decorations, Santander Insurance found.