(CNN) Boris Johnson is a Conservative British politician famous for some decidedly undiplomatic utterances. But on Wednesday he became the UK's new foreign secretary, a role in which he oversees the country's diplomats and discusses sensitive matters with his global counterparts.
The New York-born Brit is known for his colorful rhetoric over the years and distaste for political correctness. While the former London mayor has expressed considerable admiration for the U.S. over the years, he has also lit into American political leaders President Barack Obama and presumptive GOP presidential nominee Donald Trump.
The State Department, however, is welcoming his appointment. U.S. Secretary of State John Kerry congratulated Johnson Thursday, and the two pledged to work closely together as NATO allies, according to the State Department. Kerry also stressed U.S. support for a "sensible and measured approach" to the Brexit process" of the the UK's departure from the EU.
"We look forward to engaging with Boris Johnson as the new foreign secretary," State Department spokesman Mark Toner said on Wednesday after his selection. "This is something, frankly, that goes beyond a relationship, that goes beyond personalities."
Here's a list of statements made by Johnson about his native land and some of its most prominent citizens and practices.
The then-London mayor lambasted the U.S. President's Kenyan heritage in an attack on Obama's opposition to a British exit from the European Union, a cause Johnson strongly championed. The President had voiced his opposition to the pro-Brexit movement in an op-ed in the Telegraph before holding a press conference in London where he criticized the effort.
In an April op-ed in the British tabloid The Sun, Johnson recounted a story of a bust of legendary British Prime Minister Winston Churchill being removed from the White House and sent to the British Embassy when Obama became president.
"No one was sure whether the President had himself been involved in the decision. Some said it was a snub to Britain. Some said it was a symbol of the part-Kenyan President's ancestral dislike of the British Empire -- of which Churchill had been such a fervent defender."
In the same op-ed, Johnson justified his case for a British exit from the European Union.
"The Americans would never contemplate anything like the EU, for themselves or for their neighbors in their own hemisphere. Why should they think it right for us?"
Johnson went on to say a British EU exit would be beneficial to Americans, and make Britain, "even better and more valuable allies of the United States."
While Johnson may find common ground with the presumptive GOP nominee in disparaging Obama's Kenyan roots, he hit Trump himself in December after the billionaire businessman implied that areas of London were dangerous due to radicalization.
'The only reason I wouldn't visit some parts of New York is the real risk of meeting Donald Trump."
Trump on Brexit: America is next
Much to Johnson's chagrin, he was later mistaken for Trump on the streets of New York City.
"I am genuinely worried that he could become president. I was in New York and some photographers were trying to take a picture of me and a girl walked down the pavement towards me and she stopped and she said, 'Gee is that Trump?' It was one of the worst moments."
Before becoming Britain's top diplomat, Johnson had an awkward relationship with America's erstwhile top diplomat and now presumptive Democratic nominee. It started in 2007 when he ridiculed Clinton's physical appearance in his Telegraph column:
"She's got dyed blonde hair and pouty lips, and a steely blue stare, like a sadistic nurse in a mental hospital."
Johnson attempted in the same op-ed to justify a second Clinton presidency with another dig:
"For all who love America, it is time to think of supporting Hillary, not because we necessarily want her for herself but because we want Bill in the role of First Husband. And if Bill can deal with Hillary, he can surely deal with any global crisis."
However, more recently Johnson has backed off from his comments, calling the former first lady "particularly gracious and charming" in 2015.
"She was so nice and so kind that even in that article she found something to agree with."
The former London mayor did not let Mitt Romney get off easy in 2012 when the GOP presidential nominee questioned London's preparedness for the summer Olympic games.
"I hear there is a guy called Mitt Romney who wants to know whether we're ready. He wants to know whether we're ready. Are we ready? Are we ready? Yes we are."
When he was visiting Iraq in 2015, Johnson couldn't help making fun of former "NBC Nightly News" host Brian Williams when the anchor was under fire for lying about his reporting experiences.
"You get in trouble over here. I was nearish to the front line. I wouldn't say bullets were wanging over my head."
In 2015, Johnson, who was thought to be on track to becoming Britain's next conservative prime minister, said he would renounce his U.S. citizenship. Part of Johnson's reasoning was to avoid paying U.S. taxes.
"I think, it's absolutely outrageous. Why should I? I think, you know, I'm not a -- I, you know, I haven't lived in the United States for, you know, well, since I was five years old."
It wasn't the first time the former London mayor said he would give up his U.S. passport. Johnson threatened to renounce his citizenship in 2006 when he was stopped from entering the U.S. with a British passport.
"As far as I can interpret the psychology of the rule, which has only been applied since 9/11, it is part of America's new them-and-us mentality, the Manichaean division of the world into Americans and non-Americans, obliterating any category in between. 'Listen, buddy,' the Americans seem to be saying, 'you got a right to be American? Then you do us the courtesy of travelling on the world's number one passport when you come here. What you got to be ashamed of, boy?'"