(CNN) President Donald Trump told a group of Democratic senators Tuesday that he'd be a "big loser" if the Republicans' plan to overhaul the tax system is signed into law, multiple people with direct knowledge of the call told CNN.
Trump, who said he made his assumption based on a conversation with his accountant, also said the GOP's plan to repeal the estate tax was a toss-in because the plan is "just so bad for rich people."
Trump spoke on the phone to the group of Senate Democrats who met with senior White House adviser Gary Cohn and legislative affairs director Marc Short in the Library of Congress, Democratic Sen. Sherrod Brown of Ohio told reporters.
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The President's phone call was a surprise to Sen. Joe Manchin, who organized the meeting. Trump called in through Cohn's phone, and Cohn put him on speaker. Trump spoke for about 10 minutes during what was the 6 a.m. hour local time in South Korea.
Sen. Tom Carper described the call as "a nice touch," but said that Trump did more talking than listening on the call, while Cohn and Short fielded more of the questions and comments.
Sen. Chris Coons said there was some "vigorous back and forth" and that every senator spoke in the meeting and "expressed our deep frustration" that they haven't been included much in the process.
"I think nearly all of us at some point said the idea that the tax bill is introduced on a Thursday and marked up on a Monday doesn't give the kind of process for participation ... that's appropriate for something that should be comprehensive tax reform," he said, a reference to Republicans' ambitious plans to pass a tax bill before year's end.
Manchin said one of the questions Democrats raised was whether there was a possible failsafe that would nullify the law if there wasn't as much growth as expected.
Sen. Ron Wyden, the top Democrat on the Senate finance committee, said senators also pushed back on the White House selling the plan as a middle-class tax cut.
Brown said the President made the pitch once again on the call.
"The President said rich people get hurt in this bill. That's what he said," Brown told reporters.
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Manchin said he organized the meeting because he wanted Democrats to have more input in the process. Some of the same Democrats attended a bipartisan meeting at the White House less than a month before, and multiple senators described Tuesday's meeting as a conversation about process rather than negotiations on the specifics.
At least 12 Democratic senators were in attendance, including: