The White House is considering making the argument that President Trump has not officially been impeached, given that House Speaker Nancy Pelosi has not transmitted the articles of impeachment to the Senate, two sources involved in the president's impeachment defense told CBS News.

The House voted to impeach Mr. Trump on two articles of impeachment — abuse of power and obstruction of Congress — on Wednesday. However, Pelosi told reporters on Thursday that the House would wait to deliver the articles until the Senate had laid out the rules for the trial.

"When we see the process that's set forth in the Senate, then we'll know the number of managers we'll have to move forward, and who we would choose," the California Democrat said. The House must vote on a resolution designating impeachment managers to prosecute the case against Mr. Trump in the Senate before delivering the articles. 

The White House is considering making the case that Mr. Trump has not been impeached based on an opinion piece by Harvard Law Professor Noah Feldman on Bloomberg's opinion page Thursday. Feldman was one of the legal experts called by Democrats to testify before the House Judiciary Committee earlier this month and has advocated for Mr. Trump's impeachment and removal from office.

"Impeachment as contemplated by the Constitution does not consist merely of the vote by the House, but of the process of sending the articles to the Senate for trial," Feldman wrote in Bloomberg. "Both parts are necessary to make an impeachment under the Constitution: The House must actually send the articles and send managers to the Senate to prosecute the impeachment. And the Senate must actually hold a trial."

"If the House does not communicate its impeachment to the Senate, it hasn't actually impeached the president. If the articles are not transmitted, Trump could legitimately say that he wasn't truly impeached at all," Feldman wrote.

The sources told CBS News that the White House views Pelosi's delay as "a Christmas gift." They plan to use the delay to argue that the Democrats have so little faith in their own case for impeachment, they are too scared to trigger a trial they know they will lose. The two sources also say that the president, while "angry" about what he views as an unfair process, is actually in a "very good mood," and feels confident he can win the messaging war via Twitter while lawmakers are back home for the holidays.

A senior White House official said the White House might pursue that line of messaging, but the White House is also in a "wait and see" attitude over the Christmas holiday. Right now, the official said they preferred to focus on "happy" messaging, not "flogging" impeachment messaging over the holidays. 

Republicans in Congress are already making this argument. Senate Majority Leader Mitch McConnell said in a speech on the Senate floor Thursday that Pelosi's decision to withhold the articles from the Senate shows Democrats "may be too afraid to even transmit their shoddy work product to the Senate." House Minority Leader Kevin McCarthy echoed those comments: "She's admitting defeat by not sending them. By refusing to send impeachment over, she knows its outcome is not good."

Pelosi and Democrats in the House and Senate are trying to pressure the Senate to call for more documents and for witnesses who did not testify in the House impeachment proceedings because the White House prevented them from appearing.

"I told leader McConnell that we would not support any trial without witnesses or documents," House Minority Leader Chuck Schumer said Thursday.

Mr. Trump's legislative director told CBS News that Mr. Trump is "baffled" by the possibility that Pelosi might withhold articles of impeachment from the Senate for an extended period of time.

"I think the president is completely baffled at the theory that Nancy Pelosi appears to have that somehow holding back impeachment articles will leverage some sort of specific behavior out of the Senate," Eric Ueland told CBS News chief Washington Correspondent Major Garrett in an interview for "The Takeout" podcast. 

Ueland suggested that holding the articles could be "constitutionally questionable." He also said it would be "extraordinarily unprecedented" if articles were to be withheld in order to force a legislative outcome.

In a rare interview that will air Sunday, the president's daughter, Ivanka Trump, told "Face the Nation" moderator Margaret Brennan that her father was "energized" by his impeachment, which she called "the first purely partisan impeachment."  

— Kathryn Watson contributed reporting