Alexander Vindman, the Army lieutenant colonel and top Ukraine expert on the National Security Council who testified on Capitol Hill last month, works with the whistleblower who filed a complaint against President Trump, according to former White House officials.

The Washington Examiner has established that the whistleblower is a career CIA analyst who was detailed to the NSC at the White House during the Obama administration and left during the first year of the Trump administration. During the Obama administration, the whistleblower worked on Ukraine issues with 2020 Democratic candidate Joe Biden, who was then vice president and designated as the point man on Ukraine. It is likely that the whistleblower traveled on Air Force Two at least one of the six visits that Biden made to Ukraine.

Now, the Washington Examiner has confirmed that the whistleblower continues to work within the U.S. intelligence community on Ukraine and related regional issues. Separately, the Washington Examiner has established that Eric Ciaramella, who was named by one outlet last week as the whistleblower, is now a deputy national intelligence officer for Russia and Eurasia on the National Intelligence Council, reporting to the director of national intelligence. During the Obama administration and the start of the Trump administration, Ciaramella was Ukraine director on the NSC, the post Vindman now holds.

A former Trump White House aide told the Washington Examiner: "It is close to a mathematical certainty that [Vindman and the whistleblower] know one another and that [the whistleblower] is being used to provide analytical support to the National Security Council on the topics of Russia and Ukraine. And that is where they would have crossed paths. They would know who one another are.”

A second former Trump White House official said they believed the whistleblower first met Vindman in Ukraine. “Vindman was [stationed] at the embassy and [the whistleblower] was traveling there a lot. This was during the Obama administration. Also, [the whistleblower] was [still working on Ukraine issues] after he left the NSC. So, I assume he would have had a lot of interaction with Vindman since they had the same portfolio.”

Vindman, 44, who joined the NSC in July 2018, around a year after Ciaramella left, testified before the House Intelligence Committee last Tuesday: “I want the committee to know I am not the whistleblower who brought this issue to the CIA and the committee’s attention.”

He added, “I do not know who the whistleblower is, and I would not feel comfortable to speculate as to the identity of the whistleblower.”

Vindman and Ciaramella's respective roles on the NSC and NIC and their presence in the small world of U.S. policymakers on Ukraine mean that they almost certainly have a close professional relationship.

A book review by Ciaramella, published in the Washington Independent Review of Books in October 2017, stated: "Eric Ciaramella is a deputy national intelligence officer for Russia and Eurasia on the National Intelligence Council. He previously served on the staff of the National Security Council, where he was responsible for U.S. policy toward Ukraine."

The review was online until at least early September this year but was taken down at Ciaramella's request, Holly Smith, editor in chief of the Washington Independent Review of Books, told the Washington Examiner. It was later republished, omitting Ciaramella's biography, but a cached version of the original still exists.

In his complaint, the whistleblower stated: "I have received information from multiple U.S. Government officials that the President of the United States is using the power of his office to solicit interference from a foreign country in the 2020 U.S. election. This interference includes, among other things, pressuring a foreign country to investigate one of the President's main domestic political rivals."

Almost two weeks after the whistleblower complaint was released to the public, a second whistleblower, represented by the same lawyers as the first, stepped forward after the first whistleblower's account was criticized for being based on exclusively second-hand information. The second whistleblower was reported to be an intelligence official, and the lawyer representing him said that he had first-hand knowledge of the events described by first whistleblower.

Additionally, the second whistleblower met with Intelligence Community Inspector General Michael Atkinson but never "filed [his or her] own complaint” and “doesn’t need to," said Mark Zaid, a lawyer for both whistleblowers.

Vindman, who was the first witness to testify, is among around a dozen administration personnel who listened in on the July 25 call Trump had with Ukrainian President Volodymyr Zelensky in which the president's opponents say a "quid pro quo" occurred related to releasing foreign aid in exchange for an investigation involving Biden.

In his statement, Vindman said, “I was concerned by the call. I did not think it was proper to demand that a foreign government investigate a U.S. citizen, and I was worried about the implications for the U.S. government’s support of Ukraine. I realized that if Ukraine pursued an investigation into the Bidens and Burisma, it would likely be interpreted as a partisan play, which would undoubtedly result in Ukraine losing the bipartisan support it has thus far maintained. This would all undermine U.S. national security."