LAS VEGAS — A federal court on Tuesday blocked implementation of a rule imposed by President Barack Obama’s administration that would have made an estimated 4 million more higher-earning workers across the country eligible for overtime pay starting Dec. 1.

The U.S. District Court in the Eastern District of Texas granted the nationwide preliminary injunction that prevents the Department of Labor from implementing the changes while the regulation’s legality is examined in more detail by the court. The order comes after 21 states sued the agency to block it before it took effect.

“Businesses and state and local governments across the country can breathe a sigh of relief now that this rule has been halted,” said Nevada Attorney General Adam Laxalt, who led the coalition of states fighting the rule and has been a frequent critic of what he characterized as Obama Administration overreach. “Today’s preliminary injunction reinforces the importance of the rule of law and constitutional government.”

The regulation sought to shrink the so-called “white collar exemption” and more than double the salary threshold under which employers must pay overtime to their workers. Overtime protections under the regulation would apply to workers making up to $913 a week, or $47,476 a year, and the threshold would readjust every three years.

Laxalt said the rule would burden private and public sectors, straining budgets and forcing layoffs or cuts in working hours.

The court agreed with plaintiffs that the Department of Labor exceeds its delegated authority with the rule, and that it could cause irreparable harm if it was not quickly stopped.