US President Donald Trump enjoyed a round of golf in Scotland at his Turnberry resort before departing the UK on Sunday for a meeting with Vladimir Putin.
Mr Trump gave an exclusive interview to The Sun where he delivered his incendiary verdict on the PM's negotiating strategy. Here's what you need to know...
When did Donald Trump arrive in the UK?
Following weeks of speculation, it was confirmed on April 26 that Donald Trump was coming to the UK in July.
The trip began on Thursday, July 12 - after Trump departed Brussels following a summit of Nato leaders.
He arrived at Stansted Airport on Air Force One before being flown by helicopter to Winfield House, the home of the US Ambassador in London.
What has Trump done in the UK?
Mr Trump was treated to a lavish dinner and concert at Blenheim Palace, Winston Churchill’s birthplace.
He and First Lady Melania have largely be kept away from protests in London.
The president and his wife were the guests of honour for around 100 guests in the spectacular setting of Blenheim Palace in Oxfordshire.
After spending the night at the US Ambassador’s London resident in Winfield House, in Regents Park, the President visited Sandhurst with Theresa May on Friday.
The pair then moved on to Chequers for a working lunch and crunch talks on a range of international issues – followed by a press conference.
Trump rejoined Melania and headed to Windsor Castle for a meeting with the Queen before heading to Scotland.
May did not travel north of the border, but Downing Street insisted the President will still be a guest of the UK government during his entire trip.
Challenged whether there was an "avoid London" strategy, the PM’s deputy spokeswoman insisted No10 frequently made use of Chequers for “important bilaterial discussions”.
Who is paying for the trip?
The British government has offered to costs when Trump goes golfing in Scotland.
Treasury Secretary Liz Truss wrote to Scottish ministers to inform them they'd foot any police costs.
The interim chief constable of Police Scotland, Iain Livingstone, said the force would need up to 5,000 extra officers costing around £5million.
The country's new justice secretary Humza Yousaf said it was "completely unacceptable" to expect Scottish taxpayers to cover the bill.
Why did Donald Trump cancel his trip to the UK in February?
Theresa May was the first foreign leader to visit the 45th President at the White House in January 2017, just seven days after his inauguration, and she invited Trump on a return trip to Britain.
Before he stepped down from the role, former Scotland Yard chief Sir Bernard Hogan-Howe let slip it had been pencilled in for June.
But in February 2017 it was revealed that Trump’s visit had been delayed until at least October in a bid to avoid protests and MPs’ snubs.
They agreed to postpone it until the autumn hoping the controversy of his attempted travel ban on citizens from seven Muslim countries would die down.
In June 2017 it was said the trip was being postponed again "until people support him coming" to the UK.
Trump was then due to come to the UK in February 2018 and the White House and Downing Street looked for options for the visit — settling on an opening ceremony for the new US embassy in London.
And Mayor of London Sadiq Khan said Donald Trump should not get a full state visit and warned the red carpet would not be rolled out for him.
What was the petition to ban him from visiting Britain?
After the invitation of a state visit was first announced, campaigners staged protests across the UK urging the government to withdraw the offer because they opposed Donald Trump's policies.
Protesters were furious at his travel ban on people from six nations on national security grounds.
They were also outraged at Trump's discriminatory remarks about immigrants as well as "sexist" comments.
Online petition "Prevent Donald Trump from making a State Visit to the United Kingdom" was signed by 1.86million people.
It said he should be allowed to visit the UK - but demanded the Government withdraw the invitation of a state visit because his "misogyny and vulgarity" would embarrass the Queen.
A rival petition titled "Donald Trump should make a State Visit to the United Kingdom" gained more than 311,000 signatures.
Supporters said it would be absurd not to invite the democratically elected President when tyrants have been welcomed in the past.
MPs have debated both petitions in Westminster Hall, where politicians branded Mr Trump a "petulant child" and blasted Britain's "fawning subservience" and "desperation" for a trade deal.
Foreign Office minister Sir Alan Duncan insisted the state visit "should and will go ahead" despite protests, adding: "This is a special moment for the special relationship."
What is the baby Trump balloon?
Sadiq Khan gave the green light for a giant “angry baby” version of Donald Trump to fly over Parliament during the President's visit to the UK.
But on July 13 it was taken down after only a small crowd gathered to see it raised in Parliament Square.
Campaigners had raised more than £16,000 to pay for the six-metre inflatable, and thousands signed a petition requesting it be allowed to fly.
What is the difference between a state visit and a working visit?
Donald Trump is not on a state visit to the UK, but a working visit.
A state visit is a formal visit from the head of state of a foreign country at the invitation of another head of state.
They are considered to show deeply friendly relations between the two nations and tend to be characterised by extravagant ceremonies.
Below a state visit is an official visit which generally has significantly less ceremony surrounding it.
A working visit simply means the foreign head of state is visiting the country and requires no invitation or ceremony on the part of the host nation.
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