When President Trump and Russian leader Vladimir Putin meet next month in Finland to discuss their differences, it is their similarities that may matter most.

Trump’s professed interest in having a close relationship with Putin — arguing it is better if they get along — and reluctance to criticize him have long worried critics of the Russian autocrat. The concerns have deepened as Trump has displayed a predilection for some of the governing tactics used by the Russian president.

Both men have sought to undermine institutions they see as threatening or disloyal, encouraged suspicion of anyone scrutinizing their actions, belittled opponents for tactical advantage, embraced the value of a spectacle and questioned the benefit of international institutions they have portrayed as working against their country’s interest.

Russia experts stress there is no comparison between Trump’s policies and Putin’s most draconian actions. But they worry Trump’s affinity for the Russian leader and their similar set of instincts could lead the U.S. president to make concessions at the summit on issues such as arms control, the NATO military alliance loathed by Putin and Russian activities in Ukraine, which have been condemned by the international community.

“All it would take is for Trump to say something bad about NATO when he is with Putin in front of the press,” said Alexander Vershbow, a former U.S. ambassador to both Russia and NATO in the Bill Clinton and George W. Bush administrations. “That would be bad.”

The two leaders have met twice before but each time on the sidelines of larger international gatherings, and this will be their first stand-alone summit. The White House and the Kremlin simultaneously announced Thursday that Trump and Putin will meet again July 16 in Helsinki, when Trump is in Europe for the annual gathering of leaders of NATO nations.

Trump also will make his first presidential visit to Britain on the same trip. By adding the Putin meeting, Trump symbolically elevated the U.S.-Russian relationship to a kind of parity with the U.S. relationship with its closest ally and with the nearly 70-year transatlantic NATO partnership.

While the NATO meeting and Trump’s trip to Britain could highlight recent tensions with allies over trade and the United States’ leadership role in the world, his meeting with Putin could underscore the similarities between the two men that concern their critics.

“He is taking a much more transactional, sort of zero-sum-game approach to foreign relations and to trade,” Vershbow said of Trump. “Certainly, zero-sum is a term you can almost always apply to Putin’s view of world affairs.”

Their meeting also will put a spotlight on special counsel Robert S. Mueller III’s investigation into Russia’s interference in the 2016 election and whether anyone in the Trump campaign worked with Moscow.

Trump has expressed a willingness to take Putin’s word that Russia did not seek to influence the election despite the conclusions of the U.S. intelligence community, while deriding Mueller’s investigation as a “Witch Hunt!”

Some of Trump’s critics said his umbrage at the Justice Department investigating his campaign has hints of the L’etat c’est moi — the state is me — attitude that Putin would appreciate.

“For Trump, I think he sort of feels that the justice apparatus should work for him — not him the president of the United States, but him, Donald Trump,” said Kelly Magsamen, a former senior Pentagon and National Security Council aide. “He doesn’t think of the democracy as an institution. He thinks of the presidency as him.”

Much like Putin, Trump encourages his most loyal supporters to suspect partisan bias in the scrutiny of presidential actions and turns criticism back on the critics.

“Russia continues to say they had nothing to do with Meddling in our Election! Where is the DNC Server, and why didn’t Shady James B. Comey and the now disgraced FBI agents take and closely examine it? Why isn’t Hillary/Russia being looked at? So many questions, so much corruption!” Trump wrote Thursday on Twitter. Comey is former director of the FBI; DNC refers to the Democratic National Committee, while Hillary is a reference to Hillary Clinton.

Trump went on to attack Mueller himself, asking in a separate tweet “When is Bob Mueller going to list his Conflicts of Interest? Why has it taken so long? Will they be listed at the top of his $22,000,000 Report?”

Both leaders are also fond of using the spectacle of big events to highlight their leadership — something that could be on display in Helsinki.

Trump praised Russia’s staging of the World Cup this month while talking up the 2026 contest, which will be held in North America.

“I think the venue has been fantastic. They really have shown something very special,” Trump said Wednesday, referring to Russia. “I fought very hard to get it to the United States, Mexico and Canada, as you probably have heard.”

Both men also regard alliances and cooperative decision-making with deep suspicion.

“The things they share in common are clearly no affinity for democratic values, first and foremost,” said Magsamen, now vice president for national security at the liberal Center for American Progress. “Trump is just basically aloof from democratic values and why they are important.”

Putin has largely silenced a once-boisterous political opposition and sidelined independent media. His government is accused of skewing elections and jailing and killing opponents.

“Putin is totally cynical about Western democracy, checks and balances, rule of law. He thinks it’s all just a facade, and our system is as corrupt and cynical as his system,” Vershbow said.

Trump has publicly shown a lack of concern with Putin’s harsh actions, and he alarmed some of his advisers when he congratulated Putin in March on his election victory.

For the summit, Trump is banking on being able to establish a friendly relationship with Putin, brushing off the idea he should take an adversarial approach to a man he has sometimes praised. In Putin he sees someone he can do business with, and he is keen to put a personal stamp on one of the most important and difficult U.S. foreign policy relationships.

Trump told reporters Friday that having a relationship with Russia is “a good thing” that can help foster peace. He said the discussion would cover Ukraine, Syria and elections, among other topics.

“We don’t want anybody tampering with elections,” Trump said as he traveled to his New Jersey golf resort.