Queen Elizabeth II and Prince Philip will be the only members of Britain's royal family attending the funeral of the country's first female prime minister, Margaret Thatcher. The Duke and Duchess of Cambridge -- Prince William and Catherine -- are pictured here at the Cheltenham Festival at Cheltenham Racecourse on March 15, 2013.
Thatcher funeral: RSVP not attending —
Queen Elizabeth II and Prince Philip will be the only members of Britain's royal family attending the funeral of the country's first female prime minister, Margaret Thatcher. The Duke and Duchess of Cambridge -- Prince William and Catherine -- are pictured here at the Cheltenham Festival at Cheltenham Racecourse on March 15, 2013.
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[File photo] Prince Charles and his wife, Camilla, Duchess of Cornwall will also miss the funeral proceedings. In this 2009 photo, Prince Charles and Margaret Thatcher pose with Chelsea pensioners as they attend the opening of a new infirmary at the Royal Hospital Chelsea in London.
Thatcher funeral: RSVP not attending —
[File photo] Prince Charles and his wife, Camilla, Duchess of Cornwall will also miss the funeral proceedings. In this 2009 photo, Prince Charles and Margaret Thatcher pose with Chelsea pensioners as they attend the opening of a new infirmary at the Royal Hospital Chelsea in London.
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[File photo] Former Prime Minister Margaret Thatcher stands with Prince Charles, then Prime Minister Tony Blair and Camilla, Duchess of Cornwall, during a Falklands War ceremony on June 17, 2007, in London.
Thatcher funeral: RSVP not attending —
[File photo] Former Prime Minister Margaret Thatcher stands with Prince Charles, then Prime Minister Tony Blair and Camilla, Duchess of Cornwall, during a Falklands War ceremony on June 17, 2007, in London.
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[File photo] Prince Charles' youngest son, Prince Harry, will also not be attending. Here, he talks with In-Pensioners at the Margaret Thatcher Infirmary at the Royal Hospital Chelsea on June 9, 2011, in London.
Thatcher funeral: RSVP not attending —
[File photo] Prince Charles' youngest son, Prince Harry, will also not be attending. Here, he talks with In-Pensioners at the Margaret Thatcher Infirmary at the Royal Hospital Chelsea on June 9, 2011, in London.
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[File photo] Nancy Reagan, the widow of former U.S. President Ronald Reagan -- Thatcher's great political friend and ally -- is also unable to attend. She is pictured here with Margaret Thatcher at 10 Downing Street, during a visit to London on July 22, 1986.
Thatcher funeral: RSVP not attending —
[File photo] Nancy Reagan, the widow of former U.S. President Ronald Reagan -- Thatcher's great political friend and ally -- is also unable to attend. She is pictured here with Margaret Thatcher at 10 Downing Street, during a visit to London on July 22, 1986.
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[File photo] Margaret Thatcher with U.S. President George H.W. Bush in the White House Oval Office, before receiving the medal of Freedom in an East Room ceremony on March 7, 1991. Bush has confirmed he will not be attending Thatcher's funeral.
Thatcher funeral: RSVP not attending —
[File photo] Margaret Thatcher with U.S. President George H.W. Bush in the White House Oval Office, before receiving the medal of Freedom in an East Room ceremony on March 7, 1991. Bush has confirmed he will not be attending Thatcher's funeral.
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[File photo] Former U.S. President George W. Bush will also miss the proceedings. Here he looks over the field on Opening Day at Rangers Ballpark in Arlington, Texas, on April 1, 2011.
Thatcher funeral: RSVP not attending —
[File photo] Former U.S. President George W. Bush will also miss the proceedings. Here he looks over the field on Opening Day at Rangers Ballpark in Arlington, Texas, on April 1, 2011.
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[File photo] South African anti-apartheid leader and African National Congress (ANC) member Nelson Mandela (R) shakes hands with then British Prime Minister Margaret Thatcher on the steps of 10 Downing Street on July 4, 1990. Mandela has turned down his invitation.
Thatcher funeral: RSVP not attending —
[File photo] South African anti-apartheid leader and African National Congress (ANC) member Nelson Mandela (R) shakes hands with then British Prime Minister Margaret Thatcher on the steps of 10 Downing Street on July 4, 1990. Mandela has turned down his invitation.
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[File photo] Former Soviet leader Mikhail Gorbachev is not planning to attend for health reasons, Vladimir Polyakov at the Gorbachev Foundation in Moscow told CNN. Gorbachev is photographed shaking hands with Margaret Thatcher at Chequers on December 16, 1984.
Thatcher funeral: RSVP not attending —
[File photo] Former Soviet leader Mikhail Gorbachev is not planning to attend for health reasons, Vladimir Polyakov at the Gorbachev Foundation in Moscow told CNN. Gorbachev is photographed shaking hands with Margaret Thatcher at Chequers on December 16, 1984.
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