Transcript for Russian banker could become key figure in Russia investigation

George, now to the Russia investigation and president trump's son-in-law and top adviser Jared Kushner caught in the crosshairs. Our chief investigative correspondent Brian Ross is here with us and, Brian, your team tracked down the Russian banker who met with Kushner. Reporter: That's right, good morning. We have a rare films of a man who could be a key figure in the FBI Russia investigation, the banker who secretly met with the president's son-in-law, Jared Kushner and is now a focus. Reporter: We found him back in Russia at a conference in St. Petersburg, but sergei gorkov trained as a spy refused to answer any questions about why he met with Kushner or what they talked about. Did you talk about American sanctions, he was asked. We have absolutely nothing to add, he said. We have a lot of meetings. The meeting under investigation took place after the electn as gorkov ran the branch office in New York under U.S. Sanctions and came at a time that the Kushner family was racing to raise money for its troubled real estate business. Did it involve the sanctions on the bank? Did it involve any business potentially? Reporter: Investigators say they want to know if Kushner went to the bank for help with this troubled investment, a skyscraper on fifth avenue, the 666 building, which analysts tell ABC news is 30% empty and cannot generate enough rental income to cover its huge debt. They borrowed 1.3 billion. That loan has to be paid back in two years. Reporter: The white house says the meeting between Kushner and gorkov was about u.s./russ relations and arranged by the Russian ambassador. The bank says, no, it was a private business discussion. This has conflict of interest written all over it. I think it's a huge problem for Kushner to be in a situation where his white house portfolio essentially allows him to have liaison with all sorts of corporate and financial institutions. Reporter: The Russian banker, gorkov could answer many of the questions the FBI and congress are asking but as of now, he's trying hard to stay out of the spotlight. Giving us what in Russian is called -- The stone wall. He continues to work in the white house and his lawyers said he'll be glad to testify before congress and answer any questions. George. Okay, Brian, thanks very much.

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