Transcript for Trump to make infrastructure push in the US

Back here at home president trump facing a big showdown from the fired former director of the FBI, James Comey, blockbuster testimony on Thursday. ABC's Mary Bruce has the latest on that. Reporter: From Chicago to los Angeles. Stand up, fight back. Reporter: And New York. Voters are demanding answers about the administration's possible ties to Russia. We have to get to the bottom of the craziness that's happening in this administration. Reporter: But this morning, the president is trying to change the subject to infrastructure. We will rebuild our roads, bridges, tunnels, highways, airports, schools, hospitals, all of it. Reporter: A week-long push to fulfill that campaign pledge including an announcement today to privatize the nation's air traffic control system. But overshadowing the president, the biggest moment yet for the Russia investigation. Fired FBI director James Comey set to tell congress his side of the story. Front and center at Thursday's hearing, Comey's private conversations with the president. And questions about whether trump urged him to drop the investigation into fired national security adviser Michael Flynn. It would be very, very troubling if the president of the United States is interfering in investigations. Reporter: But could the president try to block Comey from speaking out by invoking his executive privilege? By publicly commenting and tweeting about discussions he's had with Comey, the white house itself might have inadvertently waived the privilege. Reporter: As of right now there are no plans for the president to try to block Comey from testifying but ultimately this decision is up to the president. George. Mary, thanks. I'll anchor our coverage of the testimony live at 10 eastern. Let's check in quickly with

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