Gov. Walz came out hard against former President Donald Trump and his running mate Sen. JD Vance during his first campaign rally speech as Harris' vice presidential pick.

"Donald Trump’s not fighting for you or your family," Walz said. He never sat at that kitchen table, like the one I grew up at, wondering how we were going to pay the bills. He sat at his country club in Mar a Lago wondering how he can cut taxes for his rich friends," Walz added.

Turning his attention to Vance, Walz said, "His running mate shares his dangerous and backward agenda for this country."

"I got to tell you, I can't wait to debate the guy," Walz continued, quipping, "That is, if he's willing to get off the couch and show up."

Calling out the Republican ticket, Walz added, "These guys are creepy. And yeah, it's just weird as hell."

As Harris and Walz took the stage in Philadelphia, the Democratic National Committee announced they are officially the Democratic nominees for president and vice president.

"Vice President Harris and Governor Tim Walz officially accepted the nominations today, following the close of delegate voting on Monday, August 5th and the official certification of the roll call by Convention Secretary Jason Rae. Convention Chair Minyon Moore then certified Governor Walz as her running mate," according to the statement from DNC Chair Jaime Harrison and DNCC Chair Minyon Moore.

Harris addressed the nomination at the campaign rally, saying, "I stand before you today to proudly announce I am now, officially, the Democratic nominee for president of the United States."

During their first joint campaign rally, Vice President Kamala Harris introduced her running mate, Minnesota Gov. Tim Walz, and touted his progressive record as state governor, his background as a high school teacher and football coach and a U.S. military sergeant.

"Since the day that I announced my candidacy, I set out to find a partner who can help build this brighter future. A leader who will help unite our nation and move us forward. A fighter for the middle class. A patriot who believes as I do in the extraordinary promise of America," Harris of her search for a VP pick.

"Tim is more than a governor. To his wife, Gwen, he is a husband. To his kids, Hope and Gus, he is a dad. To his fellow veterans, he is Sgt. Major Walz, to the people of Southern Minnesota for 12 years, he was congressman. To his former high school students, he was Mr. Walz. And to his former high school football players, he was coach," Harris said.

"Coach Walz and I may hail from different corners of this great country," Harris continued, "But our values are the same."

Vice President Kamala Harris and her newly announced running mate, Minnesota Gov. Tim Walz, were met with loud applause and cheers in Philadelphia as they made their first joint appearance.

That massive crowd gave Harris and Walz a long standing ovation as they took the stage to the song "Freedom" by Beyoncé.