Washington DC - Republicans in the US House of Representatives adopted a rules package on Monday that seeks to curb the right of staffers to unionize.

Following Kevin McCarthy's election as Speaker of the House after 15 tries, Republicans on Monday joined forces to pass a rules package in a 220-213 vote.

The package, which determines how the GOP-led lower chamber will operate over the next two years, includes language seeking to strip congressional staffers of the right to form labor unions.

The move comes after House Democrats in May passed a resolution, introduced by former Rep. Andy Levin, extending unionization and collective bargaining rights to congressional workers. Staffers' right to organize was written into the Congressional Accountability Act of 1995, but the extra step of a resolution was necessary for implementation.

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Since the resolution's passage, the Congressional Workers Union has taken the House by storm, successfully unionizing the offices of Democratic Reps. Andy Levin (Michigan), Ro Khanna (California), Ilhan Omar (Minnesota), Melanie Stansbury (New Mexico), Cori Bush (Missouri), Chuy Garcia (Illinois), and Ted Lieu (California).

Staffers have also won a $45,000 base salary, overtime pay, paid parental leave, and the first contract for congressional workers in US history.

In spite of Republicans' latest union-busting efforts, congressional staffers have no intention of backing down.

"What Kevin McCarthy and his aides fail to realize is that our organizing drive – which aims to elevate workers' rights of staffers on both sides of the aisle – existed long before he cobbled together enough votes to win the Speakership, and it will continue after," the Congressional Workers Union said in a statement.

"We have no plans to stop our unionization drive, and this has in fact invigorated workers to want to utilize their collective power even more and cement our seat at the table no matter what party is in control," they continued.

"Our right to a democratic workplace is here to stay."