President Trump and Russian President Vladi­mir ­Putin will meet July 16 in Helsinki, both of their governments announced Thursday, setting the stage for a high-profile attempt to soothe tensions between the United States and Russia.

Both Trump and Putin have pursued the tete-a-tete in hopes of moving beyond friction over Russia’s interference in the 2016 U.S. presidential election and its aggression in Ukraine and elsewhere.

Shortly before the summit date and venue were announced, Trump took to Twitter, relaying that Russia continues to deny interfering in the 2016 election and airing grievances regarding the probe of special counsel Robert S. Mueller III into possible collusion between Putin’s government and Trump’s campaign.

“Russia continues to say they had nothing to do with Meddling in our Election!” Trump wrote as part of tweets in which he also disparaged former FBI director James B. Comey and once again claimed that the investigation is tainted by partisan bias.

Finland, officially neutral during the Cold War and not a NATO member, shares a border with Russia, and its president, Sauli Niinisto, has fostered a relationship with Putin.

In a statement, White House press secretary Sarah Huckabee Sanders said Trump and Putin would “discuss relations between the United States and Russia and a range of national security issues.”

Niinisto said the agenda would be decided in coming weeks, adding that Trump and Putin would “certainly discuss the overall international situation and hopefully also arms control and disarmament issues” during their meeting in the Finnish capital.

“Even small steps in reducing tensions would be in everybody’s interest,” Niinisto said in a statement.

Niinisto said he had received a joint inquiry last week from high-level U.S. and Russian officials about the possibility of hosting a meeting in Helsinki.

The summit meeting is expected to include a one-on-one meeting between Trump and Putin, a working breakfast, and a joint news conference, Kremlin foreign policy adviser Yuri Ushakov told reporters.

The Kremlin and the White House are discussing a possible joint statement that Putin and Trump would issue at the summit with a plan for improving bilateral relations, Ushakov said.

The meeting “has huge significance for both Russia and for America,” Ushakov said. “I think it will be the main international event of the summer.”

The summit date falls after previously planned stops during a trip to Europe by Trump for a NATO summit meeting July 11 and 12 in Brussels and a visit to Britain on July 13. It also allows Putin to be in Moscow for the World Cup soccer final on July 15.

Trump plans to fly to Helsinki after a weekend of golf in Scotland, officials said. Trump owns two golf courses in Scotland. The Guardian newspaper reported last month that he planned to play in Scotland with a professional golfer or possibly a member of the royal family.

Trump’s tweets Wednesday about Russian election interference underscored the scrutiny that the summit will garner in light of Mueller’s ongoing investigation.

On Wednesday, Secretary of State Mike Pompeo told the Senate Foreign Relations Committee that Trump would confront Putin over the allegations of Russian interference.

“I’m confident that when the president meets with Vladimir Putin, he will make clear that meddling in our elections is completely unacceptable,” Pompeo said.

In his tweets, Trump once again derided Mueller’s investigation as “a Rigged Witch Hunt” and suggested that law enforcement officials should instead investigate the relationship between Russia and his 2016 Democratic opponent, Hillary Clinton.

Trump’s decision to highlight Putin’s denials of Russian interference drew sharp rebukes from some Democratic lawmakers.

“The President can either believe the unanimous conclusion of our intelligence community, or he can believe Vladimir Putin,” Sen. Mark R. Warner (D-Va.), the vice chairman of the Senate Intelligence Committee, said in tweets.

“This is dangerous, this is weak, and it’s yet another slap in the face to the intelligence professionals who quite literally risk their lives to gather this kind of intelligence,” Warner wrote. “Make no mistake: the President just gave Russia the green light to once again interfere in US Elections.”

Other Democrats voiced skepticism Thursday about how much a Trump-Putin summit would accomplish.

“The President should use any meeting with Putin to confront him on Russia’s interference in our elections and the elections of our allies, the invasion of Ukraine, Russian and Syrian war crimes in Syria, and the chemical weapons attack in the U.K., among many other issues,” Rep. Adam B. Schiff (Calif.), the ranking Democrat on the House Intelligence Committee, said in a statement. “But instead, I fear that this summit will prove to be another blow to NATO and our allies, and a gift to the Kremlin.”

At the same time, U.S. lawmakers are stepping up their own engagement with Russia.

A congressional delegation will make a rare visit to Moscow and St. Petersburg from Saturday to July 5, led by Sen. Richard C. Shelby (R-Ala.), Russian Foreign Ministry spokeswoman Maria Zakharova said Thursday.

The members will meet with Russian lawmakers and other foreign officials, and “we will be glad to see and host the Americans at our ministry,” Zakharova said.

But Russian officials are playing down expectations for any major agreements at the Helsinki summit.

“I, actually, advise against using terms such as ‘breakthrough meetings’ and ‘breakthroughs,’ ” Zakharova said. “I suggest taking a fairly pragmatic, realistic attitude toward these meetings.”

The summit with Putin also threatens to further rupture Trump’s relationships with European leaders.

Trump has long sought to cultivate a warm friendship with his Russian counterpart as a means of solving in­trac­table problems around the world, and has said he admires the strength of Putin’s authoritarian rule. Earlier this month, Trump called for Russia to be readmitted to the Group of Seven nations that hold economic summits.

NATO leaders had expressed concerns about a Trump-Putin meeting taking place either before or after their planned summit.

A friendly Trump meeting with Putin ahead of the NATO meeting, they reasoned, could have exposed cracks in the alliance, which is divided over whether the West should further isolate Russia or open more dialogue and business dealings with it.

One senior European diplomat, in a recent conversation, halted mid-sentence to muse about whether it was worse for the two to meet before the NATO summit — when many alliance leaders fear the U.S. president might make big concessions to Putin without input from them — or after, when they would be unable to mop up a mess.

Both options are bad, concluded the diplomat, who spoke about the summit on the condition of anonymity in advance of the NATO gathering.

The Putin-Trump meeting could be a positive step because “lack of communication really is a problem,” said Samuel Charap, a Russia specialist at the RAND Corporation think tank in Washington.

But, he said, “in practice one has to wonder what the broader strategy with Russia is right now because there are pieces moving in so many different directions at the same time that it’s hard to make sense of it all. . . . There seem to be multiple U.S. policies toward Russia at the moment.

“We’ve seen before, though, that President Trump can swoop in and make decisions that in some cases change things pretty dramatically,” Charap said, referring to Trump’s decision to scrap military exercises with South Korea as an example.

“Part of the concern,” he said, “is that if you get the two of them [Putin and Trump] alone in the room, who knows what might happen.”

Troianovski reported from Moscow. Karen DeYoung in Washington contributed to this report.