(CNN) With a price tag of $1 billion, the new US embassy in London is one of the most expensive buildings of its kind in the world. After US President Donald Trump said he was canceling his visit to London in part because of his proclaimed outrage over the cost, it is now one of the most notorious.

In a late-night tweet, Trump blamed the Obama administration for a "bad deal" to sell the previous location in the high-end Mayfair district in central London and move to a former industrial site south of the River Thames.

In fact, the decision to move out of the Grosvenor Square building was taken under the Bush administration in 2008, principally because the building was proving harder to secure in an age of terrorist threats -- and also, in small part at least, because the US government did not wholly own it.

British property law historically allows the ground underneath buildings to be held by people and entities other than the owners of the bricks and mortar above. In this case, the land is owned by the Duke of Westminster, whose property empire controls much of the land in central London, and is leased back to the US at a nominal -- or "peppercorn" -- rent.

"In the end, we realized that the goal of a modern, secure and environmentally sustainable embassy could best be met by constructing a new facility," former US ambassador Robert Tuttle said of the decision to move.

Internal gardens intended to represent the landscape of the Grand Canyon.

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