Live updates: Harris and Walz take the stage in 1st joint campaign rally

President Joe Biden, who changed his X header to match the new Harris-Walz logo, praised Vice President Kamala Harris' pick of Gov. Tim Walz as a running mate, calling him "a strong, principled and effective leader."

"The first major decision a party nominee makes is their choice for Vice President. And Kamala Harris has made a great decision in choosing Governor Tim Walz to be her running mate," he said in his statement on X.

"The Harris-Walz ticket will be a powerful voice for working people and America's great middle class. They will be the strongest defenders of our personal freedoms and our democracy. And they will ensure that America continues to lead the world and play its role as the indispensable nation," the president added.

Biden called on all Americans to rally behind the Harris-Walz ticket.

"Every generation of Americans faces a moment where they are asked to defend American democracy. That moment is now," he said.

Former President Barack Obama released a lengthy statement on X congratulating Gov. Tim Walz for being selected as Vice President Kamala Harris' running mate.

"[Tim Walz] believes that government works to serve us. Not just some of us, but all of us. That's what makes him an outstanding governor, and that's what will make him an even better vice president," he wrote.

"By selecting Tim Walz to be her vice president from a pool of outstanding Democrats, Kamala Harris has chosen an ideal partner -- and made it clear exactly what she stands for," Obama said.

Gov. Tim Walz posted on X on Tuesday, saying he's "all in" on his new role as Harris' VP pick.

"It is the honor of a lifetime to join [Kamala Harris] in this campaign. I'm all in. Vice President Harris is showing us the politics of what's possible. It reminds me a bit of the first day of school. So, let's get this done, folks! Join us," he wrote, also linking to a donation page.

Kamala Harris has officially announced Gov. Tim Walz as her vice presidential running mate.

"I'm pleased to share that I've made my decision: Minnesota Governor Tim Walz will join our campaign as my running mate," Kamala Harris wrote in a text sent to supporters on Tuesday.

"Tim is a battle-tested leader who has an incredible track record of getting things done for Minnesota families. I know that he will bring that same principled leadership to our campaign, and to the office of the vice president."

"As a governor, a coach, a teacher, and a veteran, he's delivered for working families like his.

It's great to have him on the team," she posted on X.