White House counselor Kellyanne Conway joined Bill Hemmer and Sandra Smith as the first headliner on the revamped and expanded "America's Newsroom."

Conway said Monday the one-on-one meeting between President Trump and North Korean leader Kim Jong Un -- which is planned for 9:00pm ET on Monday -- is a critical step in moving toward a denuclearized Korean Peninsula.

“The president and Secretary Pompeo have made very clear that this is a mission of peace, and that peace impacts the entire world," Conway said.

“This is a worldwide issue and it takes President Trump’s leadership to succeed where others haven’t.”

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She said North Korea's complete, verifiable and irreversible de-nuclearization is the goal, and Kim must understand that Trump's "maximum pressure campaign" will continue unless and until that happens.

"That probably will not be achieved in a one-and-done type of meeting, but this is such a gigantic, momentous step forward that other presidents and administrations have not been able to effectuate," Conway said.

She added that Kim must also understand that dismantling his nuclear weapons program would mean that North Korea's economy would be more prosperous and its people more free.

Watch more above, and tune in to "America's Newsroom" every weekday from 9:00am to noon ET.

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