Joe Biden, the presumptive Democratic presidential nominee, has selected California Senator Kamala Harris as his running mate for the US presidential election in November.
"I have the great honour to announce that I've picked Kamala Harris — a fearless fighter for the little guy, and one of the country's finest public servants — as my running mate," Biden said in a tweet.
If elected, the 55-year-old would be the country's first black and first Asian-American vice president.
Harris would also be the nation's first female vice president.
Biden cited Harris' experience as attorney general of California, where she "worked closely" with Biden's deceased son Beau Biden, the former attorney general of Delaware.
The announcement followed a months-long search for a vice presidential candidate who could bolster the Democratic ticket during a tense election year taking place during the coronavirus pandemic and a national debate on race.
Harris ran her own campaign for president and had several contentious exchanges with Biden during the primary debates. She abandoned her campaign in December 2019, however, and threw her weight behind the former vice president.
Following Biden's announcement, Harris tweeted that she is "honored" to join Biden as the party's nominee for vice president and that she will "do what it takes to make him our Commander-in-Chief."
She has faced some backlash from the left-leaning wing of the Democratic party over her years as a prosecutor, but she nevertheless describes herself as a progressive.
President Donald Trump immediately tweeted a video attacking Harris for being too left-leaning, highlighting her call for healthcare reform.
The Trump campaign also issued a statement that painted Harris as radically left-wing.
"Joe Biden is no moderate, and with Harris as his 'political living will,' he is surrendering control of our nation to the radical mob with promises to raise taxes, cut police funding, kill energy jobs, open our borders, and appease socialist dictators," the Trump campaign statement reads.
Biden, 77, has called himself "a bridge" to a new generation of Democratic leaders, leading some to believe that he could be a one-term president and that Harris would be his successor.