And London Mayor Sadiq Khan, who has previously clashed with Trump, offered an alternative reason for why the trip may have been cancelled.
"Let's hope that Donald Trump also revisits the pursuit of his divisive agenda". "And you got the message".
Protesters outside the previous embassy with its distinctive eagle
That announcement set off a year of debate in Britain, where Trump is unpopular, and the timing of the visit was continually pushed back. A petition calling for Trump's visit to be canceled quickly gained almost 2 million signatures and petitioners promised to hold "the biggest protest ever" if the proposed visit went through.
It's now thought US Secretary of State Rex Tillerson will "cut the ribbon" instead.
In 2009, the Obama State Department agreed to sell the Grosvenor Square building where the USA embassy was located to the Qatar royal family. However, after Trump re-tweeted the far-right group Britain First - causing a diplomatic spat with May - the idea became less popular even within the prime minister's own cabinet.
"He's been to countries all over the world and yet he's not been to the one with whom he's closest", Farage told BBC Radio Four's Today programme.
Madame Tussauds said it chose to take their wax Trump figure out on a field trip after the real-life president announced he was cancelling his trip.
"But the site was compromised, rather small and was a nightmare for people living and working in the area with the various security restrictions that had to be imposed", he said.