Queen Elizabeth II welcomed US President Donald Trump for tea at Windsor Castle on Friday.
Trump walked ahead of the 92-year-old while inspecting troops and did not bow when he met her - both considered breaches of royal protocol.
Some 1.86 million people had previously signed a petition wanting to prevent Trump from making a state visit "because it would cause embarrassment to Her Majesty the Queen".
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His four-day trip to Britain is not a state visit - with the formal trappings of a carriage procession and certain banquets - but it bears many of the hallmarks, including time with the head of state.
A YouGov poll of 1,648 British adults conducted on Monday and Tuesday found that half thought Trump's working visit to Britain should go ahead, with just over a third thinking it should be cancelled.
However, the meeting with Queen Elizabeth on his first visit to Britain as US president still seems to rankle.
Just one in three (35 per cent) thought the monarch should meet Trump, as opposed to half (49 per cent) who thought she should not.
There have been 13 US presidents since Queen Elizabeth's reign began in 1952, and, including Trump, she has met them all, barring one: Lyndon B. Johnson.
