The Trump administration has withdrawn or delayed 860 proposed regulations in its first five months, the beginnings of a regulatory overhaul meant to bolster economic growth.

Federal agencies have withdrawn 469 proposed regulations compared to a fall 2016 report when Barack Obama was president, according to figures the White House budget office. This includes 19 regulations with an economic impact of $100 million or more. Another 391 regulations have been delayed for further evaluation and consideration.

"It's really the beginning of a kind of fundamental regulatory reform," Neomi Rao, head of the White House Office of Information and Regulatory Affairs, said Wednesday. A report on the regulatory actions was being released Thursday.

Federal agencies expect to complete 1,732 regulations this year, roughly a 20 percent reduction compared to the fall of 2016.

President Donald Trump's push to deregulate has led to concerns among environmentalists, labor unions and consumer watchdogs. The Natural Resources Defense Council has filed lawsuits saying that suspended rules regarding methane leaks violate the Clean Air Act. Public Citizen, a consumer advocacy group, issued a report Wednesday saying the deregulation push has been about rewarding corporate elites such as automakers and Wall Street firms.

The Trump administration said that the Obama administration introduced rules in the last five months of fiscal 2016 that imposed $6.8 billion in annual costs on the economy, while the rules imposed during its first five months have imposed no costs.

Some of the rules involve making government regulations less burdensome. The Interior Department says it plans to reduce the paperwork burden for outdoorsmen, fish restoration programs and Native American tribes. The Labor Department intends to streamline the approval process for new apprenticeship programs. The Federal Railroads Administration is planning a rule to give railroads more flexibility for choosing different types of passenger trains.

During last year's presidential campaign, Trump pledged a drastic and speedy slashing of all federal regulations.

"We're cutting the regulations at a tremendous clip," Trump said in October. "I would say 70 percent of regulations can go. It's just stopping businesses from growing."

But Rao said that any regulatory reduction through her would take time in order to be effective, saying it has to comply with the law and make sense given cost and benefit analyses. But having only been sworn into office this week, she declined to say whether her office could trim regulations as much as the president has suggested is possible.

"I'm not sure what that percentage would be," she said. "It's really hard to say. We're going to do what we can."