The prohibitions came to light Tuesday as the agency moved to delay implementation of at least 30 environmental rules finalized in the closing months of President Barack Obama’s term, a potential first step to seeking to kill the regulations.

A summary of the actions posted in the Federal Register includes a long list of regulations that include updated air pollution rulings for several states, renewable fuel standards and limits on the amount of formaldehyde that can leach from wood products. President Donald Trump signed a directive shortly after his inauguration on Friday ordering a “regulatory freeze pending review” for all federal agency rules that had been finalized that have not yet taken effect.

Emails sent to EPA staff and reviewed by The Associated Press also detailed specific prohibitions banning press releases, blog updates or posts to the agency’s social media accounts.

The Trump administration has also ordered what it called a temporary suspension of all new business activities at the department, including issuing task orders or work assignments to EPA contractors. The orders were expected to have a significant and immediate impact on EPA activities nationwide. EPA contracts with outside vendors for a wide array of services, from engineering and research science to janitorial supplies.

Similar orders barring external communications have been issued in recent days by the Trump administration at other federal agencies, including the departments of Transportation, Agriculture and Interior.

Staffers in EPA’s public affairs office are instructed to forward all inquiries from reporters to the Office of Administration and Resources Management.

“Incoming media requests will be carefully screened,” one directive said. “Only send out critical messages, as messages can be shared broadly and end up in the press.”

A review of EPA websites and social media accounts, which typically include numerous new posts each day, showed no new activity since Friday.

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White House spokesman Sean Spicer said Tuesday he had no specific information on the blackout.

“I don’t think it’s any surprise that when there’s an administration turnover, that we’re going to review the policies,” Spicer said.

Doug Ericksen, the communications director for Trump’s transition team at EPA, said he expects the communications ban to be lifted by the end of this week.

“We’re just trying to get a handle on everything and make sure what goes out reflects the priorities of the new administration,” Ericksen said.

Beyond what was stated in the internal email, Ericksen clarified that the freeze on EPA contracts and grants won’t apply to pollution cleanup efforts or infrastructure construction activities. The agency later said it would also seek to complete that review by Friday.

State agencies that rely on EPA for funding were left in the dark, with both Democratic and Republican officials saying they had received no information from EPA about the freeze.

“We are actively seeking additional information so we can understand the impact of this action on our ability to administer critical programs,” said Alan Matheson, executive director of Utah Department of Environmental Quality.

Democratic Senate leader Chuck Schumer of New York said the Trump administration should immediately reverse the media blackout and contracting freeze.

“This decision could have damaging implications for communities across New York state and the country, from delaying testing for lead in schools to restricting efforts to keep drinking water clean to holding up much-needed funding to revitalize toxic brownfield sites,” Schumer said.

The executive director for the advocacy group Public Employees for Environmental Responsibility, Jeff Ruch, said the orders go beyond what has occurred in prior presidential transitions.

“We’re watching the dark cloud of Mordor extend over federal service,” Ruch said Tuesday, referring to the evil kingdom in the epic fantasy “The Lord of the Rings.”

Ruch noted that key posts at EPA have not yet been filled with Republican appointees, including Trump’s nominee for EPA administrator, Scott Pruitt. That means there are not yet the new senior personnel in place to make decisions.

Environmentalists said the orders were having a chilling effect on EPA staff already suffering from low morale. Trump and Pruitt have both been frequent critics of the agency and have questioned the validity of climate science showing that the Earth is warming and man-made carbon emissions are to blame.

Staff at the Agriculture Department’s Agricultural Research Service also received orders not to issue any news releases, photos, fact sheets and social media posts. After an email of the order leaked to the media, USDA’s acting deputy secretary said he would ask agency officials to rescind the memo.

Spokespersons at agencies within the Transportation Department who are career employees received an email Monday morning telling them: “There will be no releases or social media until we hear from new leadership.” The one-sentence email, which was obtained by The Associated Press, came from the department’s top career spokeswoman, rather than a political appointee.

The department said in a statement that transportation officials didn’t receive any guidance on press releases and social media from the White House.

“Everybody’s being very cautious” and erring on the side of not releasing information, one DOT employee said. The employee didn’t have permission to speak publicly and spoke on condition of anonymity.

The AP reported over the weekend that staff employees at the Interior Department were temporarily ordered to stop making posts to its Twitter account after the official account of the National Park Service retweeted a pair of photos that compared those gathered for Trump’s inauguration with the much larger crowd that attended Obama’s swearing-in.

Trump later falsely claimed that more than 1 million people attended his inauguration, which Spicer insisted was the most watched in history.

In a test of what the new administration will tolerate, the official Twitter account of the Badlands National Park published a series of posts Tuesday accurately quoting climate science data that included the current record-setting high concentrations of carbon dioxide in the atmosphere. The tweets were soon deleted.

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Flesher reported from Traverse City, Michigan. Associated Press writers Mary Clare Jalonick, Joan Lowy and Darlene Superville in Washington, and Dan Elliott in Denver contributed to this report.