It’s unclear if the two have ever met in person, mainly due to Trump’s contradictory statements over the years about the nature of his relationship with Putin.
The White House said that the leaders’ face-to-face on Friday “will be a normal bilateral meeting,” as opposed to a “pull-aside” like the one former President Obama had with Putin at last year’s conference.
Tensions between the two countries are high as the U.S. maintains sanctions on Russia for its annexation of Crimea and investigates Russian interference in the 2016 presidential election — including the country’s alleged collusion with the Trump campaign.
Trump and Putin, however, have a far friendlier history. In fact, the two men have repeatedly expressed mutual admiration for each other, with Trump being widely criticized for his praise of Putin on the campaign trail and beyond.
As the world looks to Hamburg in anticipation of the two leaders’ meeting, here are 10 times Trump has complimented Putin — and vice versa.
OCTOBER 2007: “Doing a great job”
Trump’s admiration for Putin goes back at least a decade.
In a 2007 interview with Larry King on CNN, Trump praised Putin for “doing a great job” rebuilding Russia.
“Look at Putin — what he’s doing with Russia — I mean, you know, what’s going on over there,” Trump said at the time. “I mean this guy has done — whether you like him or don’t like him — he’s doing a great job in rebuilding the image of Russia and also rebuilding Russia, period.”
DECEMBER 2011: “Hats off” to Putin
Trump put his praise for Putin in print in his 2011 book Time to Get Tough, while also criticizing what he perceived to be Obama’s inept handling of the Russian president.
“Putin has big plans for Russia. He wants to edge out its neighbors so that Russia can dominate oil supplies to all of Europe,” Trump wrote. “I respect Putin and Russians but cannot believe our leader (Obama) allows them to get away with so much … Hats off to the Russians.”
JUNE 2013: “My new best friend?”
Shortly before Trump hosted the 2013 Miss Universe pageant in Moscow, he took to Twitter to ponder whether Putin would become his “new best friend” during the visit.
Asked later whether he’d met Putin during his trip, Trump declined to say, but added: “I got to meet a lot of people.”
“And you know what?” he continued, according to Politico. “They want to be friendly with the United States. Wouldn’t it be nice if we actually got along with somebody?”
JULY 2015: “I’d get along very well with Vladimir Putin”
In one of his first comments about the Russian leader since launching his presidential bid in June 2015, Trump told reporters at his golf resort in Scotland: “I think I’d get along very well with Vladimir Putin. I just think so.”
OCTOBER 2015: “Stablemates”
Trump said on CBS’s Face the Nation that he and Putin had “fantastic ratings” when they appeared on 60 Minutes “together.”
“I think the biggest thing we have is that we were on 60 Minutes together and we had fantastic ratings. One of your best-rated shows in a long time,” Trump said. “So that was good, right? So we were stablemates.”
But as TIME later reported, Trump and Putin never met during the taping of the show — because Trump was interviewed in New York while Putin was in Moscow.
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DECEMBER 2015: Flattery will get Putin everywhere
Putin weighed in on the presidential election in December 2015, praising Trump to ABC News as “a very colorful person. Talent, with any doubt.”
“He is absolutely the leader in the presidential race,” the Russian president continued. “He wants to move to a different level of relations, to more solid, deeper relations with Russia and how can Russia not welcome that – we welcome that.”
Trump reveled in the praise, saying in a statement at the time: “It is always a great honor to be so nicely complimented by a man so highly respected within his own country and beyond.”
Facing increasing criticism, Trump began to distance himself from Putin in the months that followed. But at a campaign rally in February 2016, he dismissed the idea that he should disavow Putin’s compliments.
“I have no relationship with him other than he called me a genius. He said, ‘Donald Trump is a genius and he is going to be the leader of the party and he’s going to be the leader of the world or something,’ ” Trump said, embellishing Putin’s comments.
DECEMBER 2015: “At least he’s a leader”
In a December 2015 interview on Morning Joe, Trump claimed that Putin was a better leader than Obama, and brushed aside co-host Joe Scarborough’s allegations that the Russian president “kills journalists that don’t agree with him.”
“He’s running his country and at least he’s a leader, unlike what we have in this country,” Trump said.
“I think our country does plenty of killing also, Joe, so you know,” he added. “There’s a lot of stupidity going on in the world right now, a lot of killing going on, a lot of stupidity.”
APRIL 2016: “He’s been very nice to me”
“Nice” means a lot in Trump’s book, and he has attributed the quality to Putin many times in recent years — including telling reporters at Trump Tower in September 2015 that “Putin is a nicer person than I am.”
In April 2016, Trump told Bill O’Reilly that he’d “possibly have a good relationship” with Putin, adding: “He’s been very nice to me. If we can make a great deal for our country and get along with Russia that would be a tremendous thing. I would love to try it.”
JULY 2016: “I don’t know who Putin is”
As allegations began swirling that Trump’s campaign colluded with Russia to meddle in the presidential election, Trump did an about-face on his budding bromance with Putin.
“I never met Putin,” a seemingly exasperated Trump said during his final news conference before the election. “I don’t know who Putin is. He said one nice thing about me. He said I’m a genius. I said thank you very much to the newspaper and that was the end of it. I never met Putin.”
“I have nothing to do with Putin. I’ve never spoken to him,” Trump continued. “I don’t know anything about him other than he will respect me.”
JANUARY 2017: “An asset”
In his first full news conference since winning the presidency, Trump said he would consider a good relationship with Putin an “asset.”
“If Putin likes Donald Trump, I consider that an asset, not a liability, because we have a horrible relationship with Russia,” Trump said. “Russia can help us fight ISIS, which, by the way, is, number one, tricky. I mean if you look, this administration created ISIS by leaving at the wrong time. The void was created, ISIS was formed.”