The U.S. Department of Transportation has begun the process of undoing a set of Trump-era regulations that ground agency work with industry to a halt and threatened to slow adoption of major policy goals of the Biden administration.

DOT Secretary Pete Buttigieg acted because the regulations imposed in 2019 at the department “would hamstring the department’s ability to respond quickly and effectively to the challenges we face as a nation,” it said in an emailed statement.

The agency on Wednesday repealed a 2019 regulation on rulemaking, the first step in undoing the previous administration’s restrictions. “The department is now working to revise and eliminate additional limitations” on how it can function as it tries to address the Covid-19 pandemic, climate change and other major issues, the DOT said.

“The department is also reviewing its internal policies and procedures to ensure that they are consistent with the administration’s objectives and priorities relating to the administrative process,” it said.

The DOT was one of the few federal agencies that enacted President Donald Trump’s policies restricting enactment of new regulations into federal law, Bloomberg reported on Monday. The so-called “rule on rules” had frustrated the aviation industry because it halted government technical guidance and created hurdles to major department initiatives.

In dozens of cases, once routine guidance to industry from the Federal Aviation Administration on technically complex issues such as ground stations that control drone flights and battery safety had been put on hold, in some cases for years, according to public records, a trade group and multiple people familiar with its impacts.

The DOT under Secretary Elaine Chao, following the policies Trump laid out in a series of executive orders, had imposed new restrictions on guidance documents, such as legal reviews and cost estimates. The result was that most of the work had ground to a halt, according to the records.

The law also added other hurdles to enacting major regulations, including the potential for public hearings.

Steven Bradbury, the former DOT general counsel who helped craft the rules that were repealed, said they were intended to spare industry from additional costs and to ensure they met legal requirements. He was unaware that they had led to lengthy delays, he said.