11 December 2012 Last updated at 10:22 ET
The protest was expected to be one of the biggest in Michigan’s history
A mass protest is under way at the capitol in the state of Michigan as lawmakers seemed set to pass a measure limiting labour union powers.
Republicans, who control the state legislature, plan to ban a requirement that workers pay union fees as a condition of employment.
The so-called “right-to-work” bill could be signed into law by Michigan Governor Rick Snyder later this week.
If the measure succeeds, Michigan would become the 24th right-to-work state.
Thousands of protesters gathered in the state capital of Lansing on Tuesday morning, ahead of what could be final votes on the bill.
One demonstrator, Sharon Mowers, who is a member of United Auto Workers and has worked at General Motors for 13 years, said she was worried that passage of the bill would mean lower wages.
“People don’t understand the labour movement,” she told the Associated Press. “They don’t understand the sacrifices people made to get us to this point.”
Inside, on the third floor of the capitol, dozens of people circled the rotunda and chanted: “This is our house!” as they waited to get into the public gallery, the Detroit Free Press reported.
The newspaper added the demonstrations were expected to be one of the largest in history of Michigan, a union bastion.
Wrangles over right-to-work laws have played out over weeks in some states, but the bill under consideration in Lansing was introduced only last week.
Proponents say the measure would bring more jobs and economic benefits to Michigan, while opponents say the laws are designed to weaken unions and would lead to lower wages.
In an interview with a local news outlet on Tuesday, Governor Snyder called the measure “good legislation”, adding that the law was designed to give workers a choice.
“This is about being pro-worker,” Gov Snyder said.
But on Monday, President Barack Obama spoke out against the law during an appearance in Michigan to discuss a separate matter, his plan to avoid nationwide tax rises and deep spending cuts due to take effect next year.
“These so-called right-to-work laws, they don’t have anything to do with economics; they have everything to do with politics,” President Obama said.
“What they’re really talking about is giving you the right to work for less money.”
Opponents of the bill fear that if the legislation passes in Michigan, where the US car industry is based, it could give the right-to-work movement its biggest boost yet, correspondents say.
Although nearly half of US state have right-to-work laws, Michigan would be only the second state to pass such a law in the last decade, following Indiana earlier this year.