During an online fundraiser Monday night, Biden added: “It’s going to be tough, there’s not much I can do about it now except talk about it, and expose it, but it is a serious concern. It is truly a violation of our sovereignty.”
And in an interview on MSNBC, Biden said Russian President Vladimir Putin “knows I mean what I say.”
The Democratic leaders said in a letter to FBI Director Christopher Wray on Monday that they are concerned that Congress appears to be the target of a “concerted foreign interference campaign” to influence the 2020 presidential election.
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They asked Wray for an all-members, classified briefing on the matter before the August recess.
The letter from House Speaker Nancy Pelosi, Senate Democratic leader Chuck Schumer and the top Democrats on the House and Senate intelligence committees contain no details about the threats, though they describe them as serious and specific.
“We are gravely concerned, in particular, that Congress appears to be the target of a concerted foreign interference campaign, which seeks to launder and amplify disinformation in order to influence congressional activity, public debate, and the presidential election in November,” wrote Pelosi, Schumer, House Intelligence Committee Chairman Adam Schiff, D-Calif., and Virginia Sen. Mark Warner, the top Democrat on the Senate Intelligence panel.
A congressional official familiar with the letter said that there was a classified addendum “to ensure a clear and unambiguous record of the counterintelligence threats of concern.”
The person, who was granted anonymity to describe the confidential letter, said the addendum largely draws from the executive branch’s own reporting and analysis.
The FBI said it had received the letter but declined further comment.