Transcript for Russian ambassador emerges at center of Trump campaign controversy

At the center of the firestorm is the Russian ambassador who met with at least five members of president trump's team. ABC's chief investigative correspondent Brian Ross takes a closer look at sergey kislyak. Reporter: As a career Russian diplomat, sergey kislyak, the ambassador to the United States is skilled at public speaking, delivering what the FBI calls utter falsehoods. The government of Russian Federation is not enrolled in any hacking of the type you are discussing. Reporter: And now the ambassador claims the meetings he had with key members of the trump campaign before and after the election were nothing unusual, not connected to the hacking. We do not interfere into internal affairs of the united States. Reporter: Other Russian diplomats are defending kidman on Twitter saying the U.S. Media has hit rock bottom and questioning of critics even know what a diplomat's job is and now the contacts between Putin's Kremlin and some of trump's closest advisers are at the center of the FBI and congressional investigations. We need to know is anyone compromised? Are there risks to the country because someone is compromised? Reporter: Especially because some of the Americans involved are accused of not telling the truth about their meetings with the ambassador. One aspect of the investigation involves a tight focus on the week of the Republican convention in July of last year. July 18th, the party's official platform gives a big victory to Russia by downgrading U.S. Support for uconkraine. July 20th. Ambassador kislyak meeting with senator sessions and trump adviser Carter page at the convention. Something page later tried to deny. I had no meetings, no meetings. Reporter: July 21st, Donald Trump accepts the Republican nomination for president. Thank you. Thank you very much. Reporter: And the very next day July 22nd wikileaks posts the first of the hacked democratic party e-mails. Brian Ross, ABC news, New York. Okay, a lot to talk about here. So, let's bring in political analyst Tara setmayer. Good morning. Let's talk about these tweets and they continue to come from the president about the allegations of wiretapping. Here's one of them. Is it legal for a sitting president to be wiretapping a race for president prior to an election? Turned down by court earlier. A new low. He then goes on to compare it to Nixon and watergate and refers to Obama as a bad or sick guy. What is this all about? Well, it's clearly all about deflection. Donald Trump, he has a mentor, I think in another tweet he takes about mccarthyism. His mentor was Roy cone who was one of the chief counsels during Mccarthy's trials and hearings back in those times, so he was taught to double down on things and never apologize so this is his way instead of having a mature investigation letting things go through the intelligence committee perhaps having a special prosecutor, investigating what's going on with these contacts with Russia, now the president is throwing this out here to get us to start talking about this now and these rather Hieber bollic comparisons to mccarthyism or Nixon instead of paying attention to what's going on with their contacts. Was there wiretapping? Well, we don't know. I mean, for the president to put something like that out there, that is a really wild accusation. We do know there has been reporting that there were FISA requests because there were people in the intelligence community, our intelligence community was very curious about some of these contacts between trump campaign officials and Russia which I think was a legitimate concern given how we know Russia can be and their posture and their interference in our election, there were requests, FISA court requests for these wiretaps. Now, whether that was actually done in trump tower. Whether that was to the degree and detail that president trump is now saying, we just don't know that yet so I find it irresponsible for the president of the United States to levy these. You identify as a conservative commentator. I want to mention that. The other tweets and there are many have to do with Jeff sessions, of course, Donald Trump is sticking by his ag and says just out the same Russian ambassador that met Jeff sessions visited the Obama white house 22 times and 4 times last year alone. That's a false equivalency, is it not. I think so. No one is disputing -- a typical tactic by trump and his surrogates. No one is disputing whether Jeff sessions in his capacity ace senator in the armed services committee should have met with the Russian ambassador. That is Normal procedure for elected officials. I worked on capitol hill for many years. I worked for a member of the foreign affairs committee. He met with foreign dignitaries all the time. So, that's not the discussion. The discussion is how forthcoming Jeff sessions was about having those meetings, if there was nothing untoward about them, he should have been forthcoming in testimony and has recused himself which I think was a good step to do thus far and he'll go back and he'll clarify his position but it's not the first official -- this is now the fourth person with the trump campaign that has these questionable contacts and wasn't completely forthright about it and lends to further question and inquiry about why. What are they hiding if anything? Sure. This story is almost certainly not gone away. Tara setmayer we appreciate your time and analysis this morning, appreciate it.

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