House Speaker Nancy Pelosi told her fellow Democrats on Tuesday that she's not yet ready to send the articles of impeachment against President Donald Trump to the Senate — but she suggested that she could be soon.

In a letter to colleagues, Pelosi, D-Calif., maintained that she wants to immediately see the Senate resolution laying out the process for Trump's trial before she transmits the articles charging Trump with abuse of power and obstruction of Congress to the Senate. That move would start the trial process in the Senate.

"Soon, the Senate will have the opportunity to honor its oath to 'do impartial justice according to the Constitution and laws,'" Pelosi wrote before arguing that the process proposed by Senate Majority Leader Mitch McConnell, R-Ky., is unfair.

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McConnell has said he plans to use the same process that was laid out in Bill Clinton's impeachment trial in 1999 — allow the House to lay out the charges and the White House to lay out its defense before having both sides answer senators' questions. When the questions have concluded, senators could then vote on whether to dismiss the case or hear testimony from witnesses.

In Clinton's impeachment trial, senators heard videotaped testimony from three witnesses.

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Pelosi and Senate Minority Leader Chuck Schumer, D-N.Y., have called on McConnell to include witness testimony in the trial rules from the outset, noting that unlike the Clinton administration, the Trump administration blocked several key witnesses from testifying before the House. McConnell has refused, and he said Tuesday that he has the votes to pass a resolution following the Clinton playbook.

"In addition, this morning, Leader McConnell said, 'We'll be glad to show [the resolution] to you when we unveil it,'" Pelosi wrote. "It is important that he immediately publish this resolution, so that, as I have said before, we can see the arena in which we will be participating, appoint managers and transmit the articles to the Senate."

The House Democratic leadership met Tuesday as members returned to the Capitol. While most Democratic lawmakers were mum on Pelosi's next moves, many said they supported her stance with the Senate and would not question her tactics.

"I'm not going to second-guess her. So far she's been pretty, pretty damn good," said Rep. Steve Cohen, D-Tenn.

Rep. Peter Welch, D-Vt., said he was confident that Pelosi would send the articles to the Senate at some point, adding that Pelosi would "figure it out" with McConnell because "that's the game that she brings, she'll figure out."