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House Speaker Nancy Pelosi is planning to put a resolution on the House floor tomorrow to address the Ukraine issue amid growing calls to start the impeachment process, sources said.

What that resolution will specifically say is still being worked out. In fact, a Democratic leadership aide said key committees are working on the language now.

A source adds Pelosi wants to do this before Thursday when Joseph McGuire, the acting director of National Intelligence, comes to the House Intelligence Committee in hopes of pressuring him to reveal the details of the whistleblower complaint.

Separately, CNN is told that Pelosi is telling members she thinks this issue is understandable for the American public, and they get it. (This is critical since her whole thing has been public support.)

Pelosi is also encouraging members of her caucus to state their impeachment position now in order to show there is a groundswell in the caucus. (As Rep. John Lewis and other Pelosi allies have done.) She is also giving that same message to freshmen.

This comes as Pelosi will meet with key committee chairmen this afternoon who are leading investigations into President Trump, ahead of a full caucus meeting at 4 p.m. ET. Pelosi is expected to address reporters after the meeting.