Trump's aides also suggested that Greenberg might be an FBI informant, the newspaper reported.
The media confirmed that Greenberg was an informant to the FBI until 2013, but found no evidence that he continued this activity after 2013.
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Former aide of Trump's headquarters Roger Stone told the publication that another staff officer, Michael Caputo, arranged for him to meet with a certain "Russian," who offered to pay him $2 million in exchange for compromising material against Clinton. His offer was rejected.
According to Stone, he replied to the informant: "You don't understand Donald Trump. He doesn’t pay for anything."
Both Stone and Caputo suggest that the informant was sent by the FBI. Greenberg denied work on the FBI in an interview with the publication, but Trump's former aides called his statement a lie.
The newspaper also asked the former aides why they had not provided information about the meeting with Greenberg to US Congress. Stone and Caputo claimed that they had simply forgotten about this meeting.
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The Washington Post interpreted the refusal of Trump's staff to pay money for compromising material against Clinton as another suspicious "contact with the Russians." In total, the newspaper counted 11 employees of Trump's staff, who "contacted the Russians" in any capacity.
One such meeting caused a lot of noise in the past, namely the 2016 meeting of the Russian lawyer Natalya Veselnitskaya and other Russian citizens with the leadership of Trump's staff, including the son of the then-future president, Donald Jr. The media assumed that it was at this meeting that Trump's management conspired with the "Russians" to get dirt on Clinton for use in the election campaign.
Special Counsel Mueller investigates the alleged connections between Trump and Russia, which are denied both in the Kremlin and in the White House. Trump said in the past that his political enemies had been conducting investigation against him back in the time of the pre-election campaign in conspiracy with some officials from intelligence services. Trump calls the investigation a "witch hunt."