REVEALED: Bolton urged House Dems to investigate Ukraine ambassador's firing two days before impeachment launched
Former Ambassador John R. Bolton speaking at the 2017 Conservative Political Action Conference (CPAC) in National Harbor, Maryland. Photo by Gage Skidmore.

Rep. Eliot Engel (D-NY) blew up President Donald Trump's claims that John Bolton kept his concerns about Ukraine to himself.

The New York Democrat, who chairs the House Committee on Foreign Affairs, revealed Wednesday that Bolton urged him "unprompted" in September to look into the ousting of former Ukraine ambassador Marie Yovanovitch.

Engel said his staff reached out to Bolton Sept. 19, about a week after he was pushed out as national security adviser, to ask if he would testify before the committee, as former Secretary of State Rex Tillerson had after his tenure.

Bolton and Engel spoke by phone Sept. 23 -- two days before House Speaker Nancy Pelosi announced a formal impeachment inquiry -- and Bolton strongly implied something improper had taken place around Yovanovitch's removal from her diplomatic post in Kyiv.

"At the time I said nothing publicly about what was a private conversation, but because this detail was relevant to the Foreign Affairs, Intelligence and Oversight Committees' investigation into this matter, I informed my investigative colleagues," Engel said. "It was one of the reasons we wished to hear from Ambassador Bolton, under oath, in a formal setting."

Although Bolton appeared to support the investigation the House had already undertaken into the president's Ukraine scheme, he refused to appear before the impeachment inquiry when invited.

Engel said he wanted to set the record straight now that Trump was calling Bolton's credibility into question, and said it was "telling" that the staunchly conservative Republican was now the "target of right-wing ire."