The US embassy in London warned Americans in the UK to keep a "low profile" and be aware of their surroundings as President Donald Trump visits in the coming days.
"Numerous demonstrations are being planned for July 12 to 14, 2018, surrounding the visit of the President of the United States to the United Kingdom," the embassy's website states.
"The majority of the demonstrations will be focused in central London on July 13, with other events planned for July 12 and 14."
The embassy said these demonstrations were expected to attract large crowds and cause road closures.
The "Demonstration Alert" issued by the embassy also tells Americans to "exercise caution if unexpectedly in the vicinity of large gatherings that may become violent".
Trump is set to visit the UK later this week after he attends a NATO summit in Brussels and before a highly anticipated meeting with Russian President Vladimir Putin in Helsinki. The president is scheduled to meet with British Prime Minister Theresa May and Queen Elizabeth during his visit.
But the president will avoid London almost entirely during his trip, which has been characterised as an attempt to avoid humiliation over the planned protests surrounding his visit.
One such demonstration, which has generated a particular amount of attention, involves a giant "Baby Trump" balloon that's set to fly over the UK capital.
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