(CNN) The Senate is expected to kick off the impeachment trial into President Donald Trump in an open session Tuesday and will move quickly into debating the organizing resolution drafted by Senate Majority Leader Mitch McConnell, according to a senior administration official involved in talks over the structure of the trial.

The official said the chamber would debate later Tuesday an amendment to McConnell's resolution drafted by Senate Minority Leader Chuck Schumer, a Democrat from New York.

While this could still change, if it stays in an open session, the impeachment managers and the President's defense team would be the ones engaged in what will likely be a contentious debate over the measures since senators are not allowed to speak during the trial.

The House impeachment managers on Monday prepared both to make their trial arguments and debate the organizing resolution, according to Democratic aides working on the impeachment inquiry.

House impeachment managers are not anticipating any new evidence to emerge that they would use at the Senate trial, the aides said. but they can't rule out that additional developments could play a role in the case, given how much has happened over the past month.

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