In her first Sunday show appearance since becoming a member of Congress, Rep. Alexandria Ocasio-Cortez (D-N.Y.) said on ABC's "This Week" that pressure to impeach President Trump grows every day, and that frustration within the progressive wing of the Democratic Party over Speaker Nancy Pelosi's resistance is "quite real."

OCASIO-CORTEZ: "I think every day that passes the pressure to impeach grows. It's justifiable. I think the evidence continues to come in and I believe that with the president now saying that he's willing to break the law to win re-election, that — that goes — that transcends partisanship. It transcends party lines. This is now about the rule of law in the United States of America. ..."

JON KARL: How real is that progressive frustration that Speaker Pelosi has said, at least so far, and she seems to be really holding a line, that she's not ready to do that?

OCASIO-CORTEZ: I think it's quite real. I believe there is a very real animus and desire to make sure that we holding this president to account.

Why it matters: Ocasio-Cortez is a member of the powerful Oversight Committee and arguably the de facto leader — or at least the most prominent national voice — of the progressive wing of House Democrats. Her claim that more freshmen Democrats support impeachment than have publicly said could become a significant factor as Pelosi continues to bat away calls to launch an inquiry, further dividing the caucus.

What he's saying: Trump later responded to some of Ocasio-Cortez's comments via Twitter, using part of her quote from the show that "I think we have a very real risk of losing the Presidency to Donald Trump" and adding, "I agree, and that is the only reason they play the impeach card, which cannot be legally used!"

Reality check: The full quote is: "I think that we have a very real risk of losing the presidency to Donald Trump if we do not have a presidential candidate that is fighting for true transformational change in the lives of working people in the United States."

Ocasio-Cortez responded to Trump's tweet on Twitter.

Go deeper: Which House Democrats publicly support impeachment