The FBI is zeroing in on a former Trump adviser the White House just can't shake

Associates of President Donald Trump have worked hard to distance themselves from Carter Page, an investment banker-turned foreign policy adviser whose ties to Russia have fueled speculation that the Trump campaign improperly dealt with Moscow in an attempt undermine Hillary Clinton during the election.

But the campaign's descriptions of Page's role - including how he got it and how long he served in it - have varied and in some cases contradict each other. The conflicting explanations have raised questions about why no one seems to know for sure, or at least isn't willing to say, who brought Page on - and why.

Page's personal and professional history offers no hint of an interest in American politics or foreign policy, except for occasional blog posts between 2013 and 2014 in which he criticized the US sanctions on Russia as "sanctimonious expressions of moral superiority" and praised Rosneft CEO Igor Sechin for his "accomplishments" in advancing US-Russia relations.

Page lived in Moscow in the early 2000s, when he was an investment banker for Merrill Lynch. He claims to have served as an adviser "on key transactions" for Russia's state-owned energy giant, Gazprom. In 2011, Page set up his own investment fund, Global Energy Capital, with former Gazprom executive Sergei Yatesenko.

On March 21, 2016, Trump named Page as a member of his foreign policy team in an interview with The Washington Post, prompting questions about how an energy consultant with no foreign policy experience landed on Trump's radar. The Daily Caller reported recently that Corey Lewandowski, Trump's former campaign manager, recruited Page to the campaign. Other reports say campaign co-chair Sam Clovis brought him on.

Page served in the Navy for five years after graduating from the Naval Academy in 1993. He drove a Mercedes and "reveled in lavish spending that sometimes seemed to exceed his means," The New York Times reported on Wednesday.

Page told the Times last month that "the half year I spent on the Trump campaign meant more to me than the five years I spent in the Navy." But the extent of his involvement with the campaign is even murkier than how he landed on it.

Page said early last month that he "spent many hours" at Trump campaign headquarters last year, referring to himself in a letter to the Senate Intelligence Committee as a "campaign surrogate." An administration official who worked with the campaign told Business Insider at the time that no one could recall having seen Page at Trump Tower, however, where the campaign was headquartered.

But a campaign adviser recently told The Washington Post that Page "was one of the more active" foreign policy advisers on a team that included terrorism analyst Walid Phares, former Pentagon inspector general Joseph Schmitz, international energy lawyer George Papadopoulos, and retired Army Lt. Gen. Joseph "Keith" Kellogg.

Page, the adviser told the Post, frequently submitted policy recommendations and requested meetings with Trump that the campaign says were never granted. He attended three dinners held for the foreign policy advisers in the spring and summer of 2016, according to the Post, and met Russia's ambassador to the US, Sergey Kislyak, at the Republican National Convention in July.

Page was evidently still meeting with the foreign policy group as late as August 19, Phares told Reuters at the time.

In September, Yahoo's Michael Isikoff, citing a Western intelligence source, reported that Page had traveled to Moscow in July - a trip that Politico reported was approved by Lewandowski - to meet with the sanctioned CEO of Russia's state-owned oil company, Rosneft.

Page has denied those reports, insisting he was only there to give a speech at Moscow's New Economic School. But the trip raised red flags at the FBI, which sought and obtained a FISA order to surveil Page's communications shortly thereafter. He is the first - and, so far, only - member of Trump's campaign to have been placed under direct FBI surveillance as a result of his ties to Russia.

The campaign scrambled to distance itself from Page in September. Jason Miller, then the Trump campaign's communications director, told The Hill on September 24 that Page had "never been a part of [the] campaign." Then-campaign manager Kellyanne Conway told CNN a day later that Page was "certainly not part of the campaign that I'm running."

But Lewandowski - who was, at least officially, the highest-ranking campaign official until June - told Reuters in August that Page had "definitely" been an adviser.

(The current administration official who worked with the campaign and spoke to Business Insider last month said Miller and Conway had never met Page, which is why they downplayed his role on the campaign.)

The Page saga took another dramatic turn in January, when BuzzFeed published a 35-page dossier detailing the Trump's alleged ties to Russia that, among other things, accused Page of serving as a liaison between the Trump campaign and Moscow during the election.

The document appeared to corroborate what Yahoo had reported four months earlier: Page took his controversial trip to Moscow, it alleged, to meet with Rosneft's CEO, Igor Sechin. There, Page was offered the brokerage of a 19% stake in Rosneft in exchange for the lifting of US sanctions on Russia, but was noncommittal, according to the dossier.

On December 7, Rosneft signed a deal to sell 19.5% of shares, or roughly $11 billion, to the multinational commodity trader Glencore Plc and Qatar's state-owned wealth fund. Qatar's sovereign wealth fund is Glencore's largest shareholder. Page was back in Moscow on December 8 to "meet with some of the top managers" of Rosneft, he told reporters at the time. He denied meeting with Sechin, Rosneft's CEO, during that trip, but said it would have been "a great honor" if he had.

The FBI reportedly used the dossier's raw intelligence about Page to bolster its case for the FISA order, according to CNN, indicating that the bureau had enough confidence in the validity of the document to corroborate it and present it in court.

"In my long experience in dealing with FISA processing, unconfirmed information about a potential target cannot (and has not been) included in the application‎," said John Rizzo, the former acting general counsel of the CIA.

"So, if the CNN report is accurate, then I have to believe that the FBI and Department of Justice concluded (and the Court agreed) that the info in the dossier about Page was reliable."