LONDON -- Queen Elizabeth II will be among the mourners at the funeral of former Prime Minister Margaret Thatcher on April 17, officials announced Tuesday.

Buckingham Palace said the queen and her husband, Prince Philip, would attend the ceremony at St. Paul's Cathedral, which is expected to draw dignitaries from around the globe.

The only other prime minister whose funeral the monarch has attended was that of Britain's World War II leader, Winston Churchill, in 1965.

Churchill was the last British leader to receive a state funeral, also at St. Paul's. Thatcher's service, a ceremonial funeral with full military honours, is not officially a state funeral, which requires a vote in Parliament.

But the ceremony features the same level of pomp and honour afforded Princess Diana in 1997 and the Queen Mother Elizabeth in 2002.

Police, royal and government officials and members of Thatcher's family are co-ordinating plans for the funeral, an operation that has been given the name "True Blue."

Thatcher's coffin will lie overnight at the Houses of Parliament ahead of the funeral, before being taken by hearse to the church of St. Clement Danes and then, on a horse-drawn gun carriage, to the 17th-century cathedral along a route lined by military personnel.

Thousands of people are expected to line the route through central London, and the queen and Prime Minister David Cameron will be joined by dignitaries from around the world inside the cathedral.

The televised funeral will be followed by a private cremation.

Early Tuesday, undertakers removed Thatcher's body from London's Ritz Hotel, where she died Monday at the age of 87. A van carrying Thatcher's casket left the hotel for an undisclosed location, where her body will remain during preparations for the funeral.