Trump has angered many in Britain in the last two years with a series of actions and pronouncements and many protests are expected.
While the many thousands are expected to line the streets and protest against Trump, politicians have become involved too.
"Under Theresa May, the U.K.is a key Trump ally, so it's important that he can't waltz in without significant opposition", Lund-Harket concluded.
The protests have already begun, police leave has been cancelled, while the prime minister and her foreign secretary are nervously preparing for any potential mishaps, gaffes or insults: Donald Trump is finally arriving in the UK.
A small demonstration is expected to take place near Blenheim Palace in Oxfordshire on Thursday, the venue for Trump's black-tie dinner with May on Thursday evening.
But Mr Khan said it was important that the United Kingdom could be "candid" with the USA as a close ally, saying "that's how special relationships work".
Trump arrives in Britain on Thursday after the North Atlantic Treaty Organisation summit in Belgium and will stay overnight at the central London residence of the United States ambassador, where a high metal security fence has been erected outside.
Despite the welcome from May, many Britons remain deeply opposed to Trump's visit.
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May has staked considerable political capital on maintaining close ties to the often capricious USA president, meaning she and Jeremy Hunt, three days into his job as foreign secretary, will be praying he can remain on message.
"If you believe children shouldn't be separated from their families, If you believe women should have control over THEIR OWN bodies, If you believe that our planet is worth protecting, If you believe that racism should be fought every step of the way, Then you better make some noise", Women's March London tweeted on Sunday.
On Friday he will visit PM Theresa May at Chequers, set to be followed by a meeting with Her Majesty The Queen at Windsor Castle.
Trump was heavily criticized but there was no vote and no ban was imposed.
Trump will spend Thursday night in London at Winfield House, the official residence of U.S. Ambassador to Britain Robert "Woody" Johnson.
"I think that's absolutely disgusting", Eugene Bibby, who runs a domestic appliance fix shop in Tommyfield Market in Oldham, told Fox News about the balloon.
"She was the first foreign dignitary to visit the USA when he became president".
John Scardino, 58, a high school teacher from the United States who has lived in Britian for 18 years and will be at Friday's protests in London, is dubious that the embassy alert would have any effect on crowd size.