He acknowledged that he “was not a direct witness to most of the events described” but said he had gathered it from multiple officials and was “deeply concerned” that the actions constituted a flagrant abuse or violation of law.
Ten days later, Senate staff members sought an explanation for the aid freeze during a briefing by State and Defense Department officials but received no further information. By this time, however, they had begun hearing reports that the delays might be tied to reports about Hunter Biden’s business dealings in Ukraine.
Mr. Atkinson forwarded the whistle-blower complaint on Aug. 26 to Joseph Maguire, who took over from Mr. Coats as the acting director of national intelligence, and declared that he had determined the complaint “appears credible.” Mr. Maguire brought the issue to the White House rather than Congress, arguing that he was obliged to do so, a decision that drew sharp criticism from Democrats.
The next day, Aug. 27, Mr. Bolton, then still the national security adviser, met with Mr. Zelensky in Kiev, the first personal visit by such a high-ranking member of the administration since Mr. Zelensky’s inauguration. Mr. Bolton, who holds deeply skeptical views of Russia, assured the Ukrainians that the United States stood behind them. He also was preparing for what was expected to be a meeting a few days afterward in Warsaw between Mr. Trump and Mr. Zelensky.
Ukrainian officials have said the aid holdup was not discussed during this visit and that they only learned about it afterward. The first report of the frozen money appeared in Politico on Aug. 28, the day after Mr. Bolton’s visit, and congressional aides were finally informed the next day.
As it happened, Mr. Trump canceled his trip to Warsaw to monitor Hurricane Dorian, which was bearing down on the East Coast. Instead, he sent Mr. Pence, who met with Mr. Zelensky.
Three House committees opened an inquiry on Sept. 9 to examine whether the aid to Ukraine was being held up for political reasons. On the same day, Mr. Atkinson, the inspector general, sent a letter to the intelligence committees informing them of the existence of the whistle-blower complaint but withholding details, including the subject.