On "Fox News Sunday," Florida Rep. Mike Waltz -- President-elect Donald Trump’s pick for national security adviser -- confirmed he met with Jake Sullivan, who currently holds the role in President Joe Biden's administration, and said that their teams are working together.

Waltz appeared to defend Biden's weapons policy reversals for Ukraine, though he called the moves "an escalation."

"Look, this is a clear escalation. And the concern has been, where is this escalation going?” Waltz said. "This was in response to, in large part, to North Korea sending troops. We've now responded by allowing these strikes deeper into Russia."

-ABC News' Fritz Farrow

President-elect Donald Trump announced Saturday that Brooke Rollins is his pick to lead the Department of Agriculture.

The seat requires Senate approval.

Rollins served in the first Trump administration, first as the assistant to the president for intergovernmental and technology initiatives and then later as the acting director of the Domestic Policy Council.

After Trump left office, she became the president and CEO of the America First Policy Institute, a conservative right-wing think tank which is made up of former Trump staff members that promotes his agenda.

-ABC News' Kelsey Walsh, Lalee Ibssa and Soo Rin Kim

President-elect Donald Trump is already leveraging his endorsement powers to fill vacated House seats around the country as he pulls members of Congress into his cabinet.

Trump encouraged Florida state Sen. Randy Fine to launch a bid for Florida's 6th District seat. Rep. Mike Waltz currently holds the seat, but Trump has tapped him as national security adviser.

"Randy Fine has my Complete and Total Endorsement. RUN, RANDY, RUN!" Trump said in a Truth Social post.

-ABC News' Lalee Ibssa, Kelsey Walsh and Soo Rin Kim

President-elect Donald Trump met with the new NATO Secretary General Mark Rutte Friday night at Mar-a-Lago, a NATO spokesperson said.

"They discussed the range of global security issues facing the Alliance," they said.

"The Secretary General and his team also met with Congressman Mike Waltz and members of the President-elect’s national security team," the spokesperson added.

-ABC News' Lalee Ibssa, Kelsey Walsh and Soo Rin Kim

President-elect Donald Trump's pick for the director of national intelligence, former Rep. Tulsi Gabbard, has little experience working with the nation's spy agencies and a long track record of echoing the Russian disinformation they work to expose and to counter -- a combination her critics claim should be disqualifying.

Gabbard, who represented Hawaii as a Democrat from 2013-2021 and ran for the party's presidential nomination in 2020 before becoming a Republican earlier this year, has been accused of harboring sympathies for the Kremlin and parroting propaganda generated by Russia to justify its invasion of Ukraine.

At the outset of the conflict, Gabbard blamed the Biden administration and NATO, claiming they had provoked Russia's aggression by ignoring what she called its "legitimate security concerns" about Ukraine potentially becoming a member of the defensive alliance.

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