LONDON The Queen becomes the country's oldest monarch on Thursday, overtaking a milestone set by her great-great grandmother, Queen Victoria.
Victoria was born on May 24 1819, and lived for 81 years, seven months and 29 days, dying in 1901.
Elizabeth, the 40th monarch since William the Conqueror took the throne in 1066, was born on April 21, 1926 and will become the oldest living sovereign at about 5 p.m., a Buckingham Palace spokeswoman said.
However there are no special events planned to mark the occasion and the Queen will be working as normal.
Elizabeth still has some way to go if she is to beat Victoria's record as the country's longest-reigning monarch. She ruled for almost 64 years and Elizabeth will break this in September 2015.
(Reporting by Michael Holden)