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Former Russia adviser Fiona Hill told Congress Thursday about her frustrations with U.S. Ambassador to the European Union Gordon Sondland, who got "involved in a domestic political errand."

Hill testified in the inquiry into President Trump's efforts to push Ukraine to conduct investigations that might benefit him politically. In her testimony, she described being angry that Sondland, who Trump put in charge of Ukraine relations, "wasn't coordinating" with other officials, noting that there's a "robust interagency process that deals with Ukraine."

She explained she was "upset with him that he wasn't fully telling us about all of the meetings that he was having," which she chalked up to the fact that "we weren't doing the same thing that he was doing."

Trump throughout the inquiry has defended his interest in investigations involving former Vice President Joe Biden and the 2016 election as coming from a desire to see Ukraine crack down on corruption. But Hill told Congress that what Sondland got involved in was "a domestic political errand," whereas other officials were "involved in national security foreign policy."

Hill also revealed that at the time, she warned Sondland, "I think this is all going to blow up." She added, "And here we are." Brendan Morrow