Associated Press President Donald Trump's lawyers are gearing up for the second day of opening arguments in his historic impeachment trial. Monday's proceedings, which will begin at 1 p.m. ET, come after The New York Times reported that former national security adviser John Bolton claims Trump personally told him he would withhold military aid to Ukraine until it launched politically motivated investigations targeting his rivals. The revelation shatters the defense team's key argument against impeachment: that there are no firsthand witness accounts about the president directly confirming a quid pro quo. Scroll down to watch the trial and follow Insider's live coverage. Visit Business Insider's homepage for more stories. President Donald Trump's Senate impeachment trial continued Monday as his defense team delivered more opening arguments.