With a $1 billion price tag, the embassy is not only one of the most expensive buildings of its kind in the world, but also perhaps one of the most notorious after US President Donald Trump last week said he was canceling a planned visit to London
in part because of his proclaimed outrage over the cost.
The new embassy, a 12-story glass cube designed by Philadelphia architecture firm KieranTimberlake, will house around 800 staff and is expected to receive 1,000 visitors daily.
The embassy occupies an almost five-acre site in an area that has been a focus of regeneration. Security requirements are tight
-- it is set back 100 feet from the street and boasts a semi-circular pond as a security measure.
Inside the glass monolith, tiny stars adorn the windows and internal gardens feature everything from cacti to ferns, in an homage to America's varied landscape.
Outside, the roof has been fitted with solar panels and a rainwater collection system for irrigation and flushing.
From concrete to glass
The new embassy is a world away from its current concrete home, designed by Finnish-American modernist architect Eero Saarinen.
The historic Mayfair site is now set to be converted into a luxury hotel by Qatari investors.
Trump criticizes deal
But don't expect any ribbon-cutting ceremonies from Trump, who last week tweeted his disapproval
of what he described as the Obama administration's "bad deal" to sell the previous location in the high-end Mayfair district in central London and move to the 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.
Some members of the US Congress have also criticized the hefty price tag.
At a hearing in 2015, Rep. Jason Chaffetz, a Utah Republican and chairman of the House oversight committee, slammed the administration's construction process as mismanaged
, resulting in a building with an "opulent-looking" glass facade that favored aesthetics over security.
However, architect James Timberlake told CNN the design met strict security requirements and the gleaming exterior was "one of the first glass embassies in the world," which conveyed an "open and welcoming" atmosphere.
A special relationship
Officials have touted the new embassy as a celebration of the special relationship between the US and UK. In December, touring the new site, UK Foreign Secretary Boris Johnson boasted that Trump would like it. "We are looking forward to welcoming the President when he comes over here. I think he will be very impressed with this building and the people who occupy it," he said.
Unfortunately for Johnson and the embassy staff, Trump doesn't appear to see it in quite the same way.