Transcript for Date and location set for Trump to hold sit-down with Putin

Just two weeks ago, we were in Singapore for the high stakes summit. We'll be in Helsinki in just three weeks, president trump and the Russian president, Vladimir Putin. Here's ABC's Martha rad dad tonight. Reporter: He has been talking up a summit with Vladimir Putin for months, and now the date is set. Well, I think we'll be talking about Syria, I think we'll be talking about Ukraine, I think we'll be talking about many other subjects and we'll see what happens. About election meddling? You never know about meetings. We'll see what happens. Reporter: They will meet in Helsinki on July 16th amid the swirling special council investigation into Russian election meddling and possible collusion with the trump campaign. National security adviser John Bolton in Moscow laying the groundwork. Russian officials say Putin told Bolton he did not meddle. Today, president trump tweeting, "Russia continues to say they had nothing to do with meddling in our election!" He has consistently heaped praise on the Russian leader. Most recently, praising Russia's hosting of the world cup. They have really done a fantastic job with the world cup. It's exciting, even if you're not a non-soccer fan. Reporter: Putin today scoring a goal for the cameras in red square. And Martha Raddatz is with us tonight. Martha, news of this summit comes as the president also ramps up his rhetoric on some of our European allies. Reporter: He certainly does, David. There is increasing strain with our allies who he'll also be meeting with next month. This is what he said at a rally last night. "The European union was set to take advantage of the united States and, you know what, we're not going to let that happen." Could be some very tense meetings. David? Martha Raddatz tonight.

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