That contrast troubles Russia experts and former U.S. officials who say that a president who famously ignored staff instructions not to congratulate Putin on winning a tainted election campaign is liable to make promises and concessions to a Russian autocrat he seems eager to please.

“What Putin brings is an ability to articulate his demands, a better knowledge of what he wants out of these discussions and a track record of knowing how to manipulate people to get what he wants,” said William Pomeranz, a Russia expert at the Woodrow Wilson International Center for Scholars.

Trump has made clear that he is eager for warmer relations with Russia — and as long as president’s mercurial nature continues to upend the global order and open doors for Moscow, Putin will be more than happy for Trump to simply continue being Trump.

Putin’s agenda for the potential summit is clear, according to experts. For Putin, the best outcome of the summit is a tacit — or even explicit — endorsement from the American president on par with the praise Trump heaped on North Korean dictator Kim Jong Un after this month’s summit in Singapore.

Such global recognition could help Putin toward some of his longer-term goals, including the recognition that Russia was right to annex a portion of Ukraine in 2014, a commitment to respect Syrian President Bashar al-Assad’s continued rule in Syria, or even a pledge to end the expansion of NATO, the North American-European military alliance that serves as a counterweight to Russian aggression.

And Trump has already endorsed another long-term Putin goal — readmission into the G-7 — a group of major world economic powers that banished Russia over its intervention in Ukraine.

While U.S. officials have their own list of demands — among them, assistance with fighting terrorists in Syria and obtaining a pledge that Moscow won’t meddle in the 2018 midterm elections — there’s no way of knowing what Trump will say once he gets in the room. Trump has thrown observers for a loop each time he talks about Putin, vowing on one occasion that he accepted the Russian leader’s belief that the Kremlin didn’t interfere in the 2016 election and even drawing widespread dismay and mockery for suggesting a possible joint U.S.-Russia cybersecurity unit to protect elections.

Trump’s unpredictability has administration officials and outside observers worried.

“I think the assumption is that Trump will go off script. What we’ve learned with his recent summit in Singapore is that he loves the focus and attention that comes with this kind of high-stakes summit,” Pomeranz said. “There is always a risk that Trump promises something that his advisers don’t want him to put on the table.”

Some in the administration have urged caution, warning that a high-profile summit with Putin would further fuel criticism that he is too close to the Russian leader, especially with special counsel Robert Mueller still probing his campaign’s connections to Moscow. But Trump — who has been fascinated by Putin for years and sometimes talks about wanting to visit Moscow as president, according to one person close to him — has dismissed those concerns, telling aides he’s not worried about the image of the meeting.

For Putin, the optics of such a high-profile summit with a U.S. president could on their own deliver a political victory, portraying him once again on equal footing, as the leader of a nuclear power. After attempting a failed “reset” of relations with Russia during his first term, President Barack Obama concluded that the best approach was to shun Putin, and essentially treat him as the leader of a fading regional power. Obama’s critics argued the cool approach allowed Russia to assert itself with insufficient pushback.

But foreign policy experts also believe Trump’s new world disorder, in which he can appear at times on friendlier terms with adversaries than traditional U.S. allies, serves Putin’s ultimate goal of ending America’s unilateral dominance over world affairs. The Russian president speaks frequently of his hope for a new “multilateral” system, and the sinking popularity of the U.S. in many European countries could help achieve that goal.

“The bipolar world we got used to in the second half of the 20th century did have a range of deficiencies but also secured something that was extremely important, namely stability,” Vladimir Chizhov, Russia’s ambassador to the European Union, said in a recent speech in Athens. “Despite all efforts within the last 20 years, a unipolar world never fully materialized — notwithstanding the illusions of those who expected to be able to manage all geopolitical processes and came to believe in their own exclusiveness.”

Russia has long tried to suggest that it is a more natural ally of the EU than the United States, and Putin could use any meeting with Trump to highlight Russia’s continued support for the Paris climate change accords, and the Iran nuclear deal — both of which Trump has repudiated — as evidence that the U.S. is now out of step with its European allies.

The potential Trump-Putin summit is expected to come either just before or after the July NATO summit, which the U.S. president will attend. European officials are deeply concerned that Trump will be more focused on his meeting with Putin than his discussions with NATO allies. The situation could mirror the recent spectacle of Trump cutting short his meeting with the G-7 leaders, angrily withdrawing his support for a joint statement and jetting off to praise Kim in Singapore.

“I think the Europeans have been worried about this meeting since Trump became president,” said Jorge Benitez, a senior fellow at the Scowcroft Center for Strategy and Security who focuses on NATO. “The optics coming out of Singapore were not good. I think it raises fears of just how much he’ll embrace Putin.”

A July get-together would be Trump’s third personal encounter with the Russia leader — the two met for the first time at the annual G-20 summit of leading economic countries in Hamburg, Germany not quite a year ago, and later met on the sidelines of the Asia-Pacific Economic Cooperation summit meeting in Vietnam.

After their first meeting last year in Hamburg, Putin and Trump agreed to work together to push for a ceasefire in the Syrian civil war, to end the conflict in eastern Ukraine and combat cybersecurity threats. There seems to have been little progress on any of those fronts.

But Trump has made clear that he is eager to develop positive relations with Russia, even sometimes to the irritation of his national security staffers. Briefing materials provided to Trump earlier this year explicitly warned the president, in capital letters, not to congratulate Putin on his election victory. Trump did it anyway.

To that end, rather than trying to take any advantage of Trump, Putin may simply want to tell Trump what a great job he’s doing, and suggest they meet again — really soon.