Buckingham Palace said the events are not part of a "mini-Jubilee"

In addition to marking her official birthday with the Trooping the Colour on 17 June, the Queen will attend a St Paul's Cathedral service on 15 June.

And members of the Royal Family will attend a service of thanksgiving at St George's Chapel, Windsor, on 23 April.

Buckingham Palace said the events were not intended to be a "mini-Jubilee".

The Queen will spend her actual birthday on 21 April at Windsor Castle where Prince Charles will host a family dinner.

A reception and lunch for people around the country who share the Queen's exact birthday will be hosted by the Queen and the Duke of Edinburgh at Buckingham Palace on 19 April.

Appropriate celebrations

And, as part of the programme of events, the monarch will also host a birthday Garden Party at Buckingham Palace for children from all over the UK.

A travelling exhibition of 10 of the Royal Collection's finest drawings by Leonardo da Vinci will travel to museums and galleries in Exeter, Aberdeen, Leeds and Cardiff over the course of 2006 as part of the celebrations.

A Buckingham Palace spokeswoman said: "This anniversary is not intended to be a mini-Jubilee but the Queen's 80th is a landmark personal anniversary.

"It's right that it should be appropriately celebrated."

Next year will also see the Duke of Edinburgh celebrate his 85th birthday on 10 June.