A man who proposed to his girlfriend at the Shard has said he had no idea Boris Johnson and a media pack would be on the observation deck at the same time.
When James Episcopou, 22, got down on one knee, the moment was captured by a host of photographers.
The couple, from Epping Forest, Essex, got engaged moments after the Mayor of London cut a ribbon at the official opening of the highest vantage point in western Europe.
Mr Episcopou, a supervisor at John Lewis, said: "I've had it planned since July last year. When tickets first came out I thought I've got to buy them, it's the perfect place to propose. Laura means everything to me and I wanted to make her feel on top of the world.
"We had no idea the media were going to be there, but when we arrived we saw Boris Johnson and there were cameras everywhere."
Miss Taylor, a 22-year-old accountant, said: "I had no idea he had planned it. I thought we were going up to look at the view.
"James asked me to come over to him because some photographers would like to take our picture. The next moment he was on one knee and proposing. I was so shocked. I said 'yes, definitely', but then I was speechless."
The proposal took place on level 72 of the Shard, just over 800ft (244m) above the capital. Mr Johnson had earlier described London's tallest building as "a most amazing place".
He said: "I don't think there's anything in London like this. It's the closest thing to being in an airplane and looking down on London. But you can walk around, you've got complete stability."
On a clear day visitors to the Shard, which towers over the city at a height of 1,016ft, are promised a spectacular view of the capital. But visibility was restricted for the dignitaries, journalists and members of the public attending the launch because of wet and cloudy weather. Some 4,800 people paid for admission on Friday - at £24.95 for adults and £18.95 for children.