House Speaker Nancy Pelosi (D-Calif.) said on CBS News' "Face the Nation" on Sunday that it is a "waste of time" to discuss what Republicans say about impeachment because "they are in denial about what has happened in the country."

"I really have a real discomfort level of responding to what Republicans say because they are in denial about what has happened in the country. So if you want to ask me about where we're going on this, I'm happy to respond to that. But I find it a waste of my time and yours to just be talking about what Republicans say. ... Let their argument stand, because it's on such quicksand that I don't even want to have it given any more visibility by my dignifying any of their misrepresentations of what they say."

— Nancy Pelosi

The big picture: One of the Republicans' main defenses against impeachment centers on the fact that the military aid for Ukraine — which the Trump administration allegedly withheld in exchange for an investigation into the president's political opponents — was eventually received.

Pelosi told CBS' Margaret Brennan that "of course" there was a link between the aid and the investigations, as EU Ambassador Gordon Sondland and top Ukraine diplomat Bill Taylor have testified, and that Trump only released the aid after the whistleblower complaint was filed.

that "of course" there was a link between the aid and the investigations, as EU Ambassador Gordon Sondland and top Ukraine diplomat Bill Taylor have testified, and that Trump only released the aid after the whistleblower complaint was filed. On the question of whether Trump's tweet during former Ukraine Ambassador Marie Yovanovitch's testimony was witness intimidation, Pelosi dodged and did not address whether it would be considered for an article of impeachment.

of whether Trump's tweet during former Ukraine Ambassador Marie Yovanovitch's testimony was witness intimidation, Pelosi dodged and did not address whether it would be considered for an article of impeachment. She called it a "mistake" and said: "I think part of it is his own insecurity as an imposter. I think he knows full well that he's in that office way over his head, and so he has to diminish everyone else."

Pelosi said there is no timetable for when the impeachment inquiry will wrap up or even whether articles of impeachment will ultimately be voted on. She was unequivocal, however, on the seriousness of the allegations, telling Brennan that "our democracy ... is at risk with this president in the White House."

"It's really a sad thing," she added. "What the president did was so much worse than even what Richard Nixon did, but at some point, Richard Nixon cared about the country enough to recognize that this could not continue."

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