Amazon Labor Union president Christian Smalls and organizers from a Starbucks union and other grassroot efforts across the country will meet with Vice President Kamala Harris and Secretary of Labor Marty Walsh at the White House Thursday, administration sources told Spectrum News Tuesday.

Organizers from unions, including the United Paizo Workers and within Titmouse Productions, Baltimore Public Library, and REI, will also be in attendance, according to sources.

The meeting comes after Amazon Labor Union successfully unionized the first Amazon facility in the United States on Staten Island in late March. On Tuesday, workers at another Staten Island facility voted against unionizing.

Smalls tweeted Tuesday he would be visiting the White House this week, but Amazon Labor Union did not immediately return request for comment. He will also be testifying in front of the Senate's budget committee Thursday alongside labor leaders and experts, committee chairman Sen. Bernie Sanders said in a release.