Vice President Kamala Harris said Monday that she and President Joe Biden are "determined to lead the most pro-union administration in America's history."

Harris made the statement while delivering a keynote address at the Greater Boston Labor Council's annual Labor Day breakfast, held at the Boston Park Plaza Hotel.

“When union workers go to work, they go to work for the entire nation,” said Harris. “When unions are strong, America is strong."

Public support for labor unions sits at its highest level in decades, with 71% of Americans approving of them. But only 10.3% of American workers are currently members of a labor union, according to 2021 data from the Bureau of Labor Statistics. Massachusetts is slightly above the national average, with 12.6% of workers being members of a union.

The vice president, who chairs the White House Task Force on Worker Organizing and Empowerment, also joined a roundtable discussion with local labor leaders, including state Attorney General Maura Healey and Sen. Ed Markey.

Among the supporters in attendance was Kylah Clay, a barista at the first unionized Starbucks in Massachusetts. Clay said she knew something was wrong when Starbucks negatively reacted to three stores in Buffalo, New York, that began to unionize last year.

“For a lot of us, it's very intimidating to organize a union in our workplace,” she said. “No one is more qualified to organize your workplace than you and your own coworkers.”

Harris said that she and U.S. Secretary of Labor Marty Walsh have worked to reduce barriers to union organizing and protect pension plans for union workers.

“Because of your support, our administration made the largest investment in a generation in our nation’s infrastructure,” she said. “Not only did we do it, we did it with strong labor protections.”

Meanwhile, officials from the Republican National Committee discredited Harris’s visit to Boston as an effort to move the focus from national politics.

“With less than 65 days to the midterms, Biden, Harris and Democrats have no message and a failed track record," said RNC spokesperson Rachel Lee. "It’s no wonder why Kamala Harris headed to deep-blue Boston instead of a battleground state."