At a reception on Friday, Queen Elizabeth spelled out the role played by the British royal family after the Olympics were revived in Athens in 1896.
"This will be the third London Olympiad. My great grandfather opened the 1908 Games at White City. My father opened the 1948 Games at Wembley Stadium. And, later this evening, I will take pleasure in declaring open the 2012 London Olympic Games at Stratford in the east of London," she said.
"Over recent months, many in these islands have watched with growing excitement the journey of the Olympic torch around the United Kingdom. As the torch has passed through villages and towns, it has drawn people together as families and communities.
Image: Actors perform during the Opening Ceremony at the 2012 Summer Olympics, Friday, July 27, 2012, in London.