The opposition research firm behind the Trump dossier crafted a memo last year that was presented to members of the Trump campaign during the infamous Trump Tower meeting as well as to a top Kremlin official.

The development adds yet another twist to a labyrinthian saga involving Fusion GPS, which commissioned the dossier as a contractor for the Clinton campaign and DNC.

At the same time that Fusion was working on the dossier, it was conducting opposition research for a Russian businessman who was fighting against the Magnitsky Act, a 2012 sanctions law opposed by the Kremlin. (RELATED: EXCLUSIVE: Oppo Researcher Behind Trump Dossier Is Linked To Pro-Kremlin Lobbying Effort)

As part of that work, according to Reuters, Fusion produced a four-page memo of opposition research on Bill Browder, a London-based financier who helped push through the Magnitsky Act.

The memo was presented at one point last year to Russia’s prosecutor general, Yuri Chaika, The New York Times recently reported. Fusion’s fingerprints on the memo were not included in the Times report.

The Times reported that Chaika was provided a copy of the memo in Oct. 2015 by Natalia Veselnitskaya, a Russian attorney who worked alongside Fusion and who also led the Russian delegation that attended the June 9, 2016 Trump Tower meeting.

That meeting is being heavily scrutinized by Special Counsel Robert Mueller and congressional committees investigating possible collusion between the Trump campaign and Russian government.

The dossier is being used as a roadmap in those investigations, though the White House, along with many Republicans, have dismissed the document’s allegations as false.

Fusion’s work with Veselnitskaya has also led to allegations that the Trump Tower meeting was a setup aimed at compromising the Trump campaign.

The meeting was attended on the Trump campaign side by Donald Trump Jr., White House adviser Jared Kushner and then-campaign chairman Paul Manafort. Veselnitskaya attended with several people, including Rinat Akhmetshin, a Russian-American lobbyist who was once in Soviet military intelligence.

There is no question that the June 9 meeting was readily accepted by the Trump campaign.

According to emails released by Trump Jr., the young real estate executive accepted the meeting after being offered dirt on Clinton.

On June 3, 2016, he was sent an email from an acquaintance who said that a “Russian government attorney” wanted to offer information on Clinton. The acquaintance, Rob Goldstone, also made reference to Russia’s chief prosecutor, who has since been assumed to be Chaika.

Trump Jr. accepted the offer, saying “I love it.”

But Trump Jr. has dismissed allegations that the meeting constituted collusion. While he has given shifting answers about what was discussed in the meeting, he has insisted that nothing of value was offered by the Russians during the 20-minute session.

Raising further questions about the meeting was a report out this week from Fox News.

The network reported that Veselnitskaya met before and after the Trump Tower conclave with Glenn Simpson, a former Wall Street Journal reporter and founding partner of Fusion. Simpson was in charge of both the dossier project and the opposition research on Browder. He attended a Manhattan court hearing with Veselnitskaya prior to her visit to the Trump building.

The contact between Simpson and Veselnitskaya has already fueled speculation that the Trump Tower meeting was a setup. Another less nefarious possibility would be that Veselnitskaya told Simpson about the meeting with the Trump team and he funneled the information to Christopher Steele, the former British spy who compiled the dossier.

In his first memo for the dossier, written 11 days after the Trump Tower meeting, Steele alleged that the Russian government was providing the Trump campaign with negative information about Hillary Clinton as part of a well-crafted collusion scheme.

The Trump Tower memo — which Veselnitskaya carried into the meeting — makes at least one reference to Clinton.

The document, which was published by Foreign Policy last month, claims that Browder, who was born in the U.S. but is now a British citizen, made illegal campaign contributions to the Clinton campaign through Ziff Brothers, a private equity firm.

Most of the rest of the memo alleges that Browder has lied about Sergey Magnitsky, his former attorney and the namesake of the Magnitsky Act. Browder alleges that Magnitsky was murdered in a Russian prison in 2009 while investigating a $230 million money laundering scheme involving well-connected Russian thugs.

Veselnitskaya has accused Browder of lying about Magnitsky’s death in order to cover up his own financial misdeeds.

Reuters did report that Simpson told the Senate Judiciary Committee in August that he did not know about the Trump Tower meeting until this July, when it was reported by The New York Times. Simpson is scheduled to meet with the House Intelligence Committee next week.

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