The National Park Service announced Monday it is withdrawing a proposal that could have made protesters repay the federal government for the cost of security at demonstrations.

Opponents said the measure would have saddled protest organizers with enormous costs, crippling their ability to protest and exercise their rights under the Constitution. The proposal would have affected gatherings on the Mall, at President’s Park, around the White House and on other federal land in the Washington area.

To obtain a permit for a protest in the District, organizers already are required to provide amenities to demonstrators, such as toilets, medical tents and cooling stations for hot days. The Park Service proposal to charge for security, announced in August 2018, would have added a hefty price tag for organizers of larger events.

“If someone called me to say, ‘I want to have a protest,’ and I said, ‘Cool, the Park Service is going to charge you $150,000 for security,’ they would hang up the phone,” Samantha Miller, an organizer with DC Action Lab, a company that helps plan demonstrations in Washington, said recently. “There are already a lot of preexisting fees that organizers get asked to pay. Add in something like a security fee, and there’s just no way most people or organizations would be able to afford it.”

About 750 First Amendment demonstrations converge on the Mall annually. The largest rallies often require additional support from Park Service personnel and Park Police to ensure safety and to limit harm to federal land, which prompted the agency to seek ways for recouping those costs.

The Park Police has requested hundreds of thousands of dollars in emergency funding over the past two years to support such events. In a statement, the Park Service said the volume and complexity of permit requests has increased substantially in recent years.

Mara Verheyden-Hilliard, executive director of the Partnership for Civil Justice Fund, said her organization was ready to file suit had the new proposals gone through.

“This is an extraordinary victory for the people of the United States,” she said. “And it says, without question, to this administration that the people of the U.S. will not be silent. They will not accept any effort to shut down their ability to speak out and to stand up for what they believe in.”

Civil rights organizations on both sides of the political spectrum had voiced opposition to the proposal. A coalition of eight organizations — led by the American Civil Liberties Union and composed of organizations that include the left-leaning Public Citizen and the NAACP, as well as the conservative Charles Koch Institute and the March for Life Education and Defense Fund — sent a letter to members of Congress in April to oppose the proposed changes.

The ACLU expressed satisfaction with Monday’s announcement.

“The National Park Service’s retreat should serve as a reminder that if the administration tries to come after our right to protest, it will have to get through thousands of ACLU members and supporters first,” senior legislative counsel Kate Ruane said in a statement.

Park Police budgets obtained by The Washington Post through the Freedom of Information Act earlier this year show the ­anti-gun-violence March for Our Lives in 2018 cost Park Police about $153,596 to secure. Park Police spent about $77,508 on security later that year for the Unite the Right 2 rally, in which a small group of white nationalists gathered near the White House as thousands of counterprotesters took to the streets to meet them.

The Park Service said it received more than 140,000 comments about the proposal. The agency also had weighed limiting the number of people who can gather without a permit.

“In response to the feedback we received from the public, the National Park Service has decided to make no changes to the regulations,” the agency said in a statement. “We appreciate that so many people are engaged and interested in the management and care of their national parks.”