The lunch is being held in the Palace of Westminster and the Prince of Wales, the Duchess of Cornwall, the Duke and Duchess of Cambridge and Prince Harry are all in attendance.
Here is the menu for the Diamond Jubilee lunch opening with wine from a Sussex vineyard.
Nyetimber Classic Cuvée 2007, Sparkling English Wine
Sandringham Apple Juice
Marinated Uist Island Salmon with Lyme Bay Crab
Fresh Herb Salad with Lemon Soy Dressing
Sancerre Sauvignon Blanc, Bué Loire Valley, France 2011
Saddle of Welsh Cambrian Mountain Lamb with Braised Shoulder of Lamb
Grilled Isle of Wight Asparagus, Jersey Royal Potatoes, Jubilee Sauce
Château Cap de Faugères, Côte-de-Castillon, France 2007
Followed by a Symphony of Dessert
Bread & Butter Pudding
Berry Compote with Sandringham Apple Sauce
This will be accompanied with:
Ceylon Tea, Fairtrade Coffee and Petit Fours
The Ceylon Bush Tea was planted by The Duke of Edinburgh during a State Visit to Sri Lanka in 1954 in the Pedro Tea plantation in Nuwara Eliya.
You can see more on the highlights from the day on our special Jubilee events web page here