This week, the White House announced that President Trump would finally be visiting Britain. The date is set for July 13.

It has been a long time coming. Since he entered office last year, there has been persistent talk of Trump visiting Britain. The United Kingdom is one of the United States’ strongest allies, and a trip to London is often on the schedule for any U.S. president. Like many of his predecessors, Trump has familial ties to Britain: His mother, Mary Anne MacLeod Trump, was born in Scotland’s Outer Hebrides.

But for over a year, no trip was scheduled. In the end — if Trump's trip goes ahead — it will have taken almost 18 months for the American leader to make it to Britain.

Britons' widespread animosity toward Trump may be the problem. Despite his recently saying that he was “very popular” in Britain, 67 percent of the British populace thinks Trump has been a “poor” or “terrible” president, according to one poll. The dislike crescendoed last fall after Trump retweeted a British fringe group’s anti-Muslim videos, with members of Parliament deriding him.

Meanwhile, Britain has had its own internal challenges over the past year as it wrestles with the complexities of the planned exit from the European Union. A state visit by the “America First” president would not necessarily be a welcome distraction for Prime Minister Theresa May, whom critics have accused of “groveling” before Trump.

So what took so long? Here's a timeline of pledges, promises and controversy surrounding Trump's long-awaited visit to London.

Jan. 20, 2017

Upon Trump’s inauguration, May congratulates the U.S. leader and says they are both committed to advancing the “special relationship between the two nations.”

“I look forward to discussing these issues and more when we meet in Washington,” May says.

Jan. 27, 2017

The British prime minister becomes the first foreign leader to meet with Trump since he takes office. The pair present a united front in public appearances, but the British government is said to be surprised afterward by the overwhelmingly negative press coverage of the trip. During a news conference in Washington, May tells reporters that Trump had accepted an invitation from Queen Elizabeth II for a state visit later that year.

Jan. 30, 2017

A petition calling on May to cancel the state visit receives more than 1 million signatures in just a few days.

Feb. 7, 2017

The speaker of Britain’s House of Commons, John Bercow, tells lawmakers that he is “strongly opposed” to Trump addressing Parliament, an honor sometimes extended to visiting heads of state. Bercow cites concerns about “racism” and “sexism” in justifying his decision.

Feb. 20, 2017

In response to the petition against Trump’s visit, which acquires more than 1.8 million signatures, British politicians debate whether the invitation to Trump for a state visit should be rescinded. Many argue that the visit should be scrapped or watered down to an official visit. Although the debate carries no legal force and some lawmakers still support the visit, it is embarrassing for the prime minister.

June 12, 2017

The Guardian reports that Trump told May in a phone call that he did not want to proceed with a visit to Britain until the British public supports his coming. The report comes after Trump attracted widespread criticism in Britain for comments about London Mayor Sadiq Khan in the aftermath of a terrorist attack in the British capital. Jeremy Corbyn, the leader of Britain’s opposition Labour Party, tweets his support for the cancellation of the state visit.

July 8, 2017

Trump meets with May at the Group of 20 summit in Hamburg. “I will be going to London,” Trump says when asked by reporters in the room whether he still plans to visit London. When pressed on timing, Trump says he will “work that out.”

Nov. 30, 2017

After Trump retweets anti-Muslim messages from a far-right activist in Britain, he faces more criticism from the British public. May blasts Trump for posting the inflammatory videos, in turn prompting an angry response from Trump:

The Telegraph newspaper quotes a “government source” as saying that the trip has been “kicked into the grass as long as it can get.”

Dec. 3, 2017

The Sunday Times of London reports that a Trump visit to London is scheduled for February so he can attend the opening of a new U.S. Embassy. The trip is to be a shorter and less formal “working visit” rather than a state visit. The next day, anti-Trump groups say they are hoping to organize the largest protests in British history when he visits.

Jan. 12, 2018

Trump says he is canceling the visit to London, justifying the move on Twitter by saying that he believes the real estate deal for the new U.S. Embassy was bad.

Former U.S. ambassadors to Britain contradict him, saying the deal (which was begun under President George W. Bush) was necessary because of safety concerns.

Jan. 25, 2018

Trump meets May during the World Economic Forum in Davos, Switzerland. The president denies reports of controversy between the two nations or the two leaders, telling May, “We love your country.” A “senior UK government source” tells the Guardian that a trip is now expected to take place in the latter half of 2018. It would be a working visit, rather than a state visit, which would still take place at some point in the future.

April 20, 2018

Citing a British government source, the Daily Mail reports that a Trump visit has been penciled in for mid-July, with July 14 the favored date. Although it would not be a state visit, the newspaper reports, Trump could probably meet the queen or other members of the royal family, in addition to May.

April 26, 2018

The White House formally announces the visit, now set for July 13. Downing Street says the visit will include “bilateral talks” with May but does not provide details.

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