The Women's March on Washington has become one of the first events to receive a permit to conduct a demonstration around the inauguration of President-elect Donald Trump. However, more than 20 other groups are still waiting to get the green light from the National Park Service.

DC police confirmed Thursday (15 December) that they issued a permit for the Women's March on Washington for 21 January, the day after Trump's inauguration. The demonstration, which is slated to be the largest of its kind as Trump takes office, is set to begin at Independence Avenue and Third Street SW, in front of the Capitol.

According to The Washington Post, the Women's March on Washington's permit application estimates around 200,000 participants.

Organisers had originally planned to rally in front of the Lincoln Memorial but were unable to secure permits.

The Park Service, which handles First Amendment permits, does not grant requests until the Presidential Inauguration Committee establishes where it will hold inauguration-related events. This policy has led some groups to claim the Park Service is hampering their demonstration planning, NPR reported.

However, Mike Litterst, a Park Service spokesman, defended the objectivity of the approach. "I think what a lot of people are missing is that this is a process and procedures that are established in the code of federal regulations and they are applied equally across the board, regardless of who had won," he said.

Left-wing pressure group Answer Coalition has nonetheless decided to challenge the Park Service's process in federal court, as it also awaits the decision on its appeal of an earlier ruling in favour of the government.

Attorney Mara Verheyden-Hilliard, with the Partnership for Civil Justice Fund, argues that preventing the protesters from expressing themselves on federal land is unconstitutional.

"When you have an incoming administration, the people have the right to communicate to that administration what they think and what they believe," she said. "And people have a right to be within sight and sound of the White House. They shouldn't have to be pushed off two miles away," she told NPR in reference to the Women's March.

Mrinalini Chakraborty, an organiser for the Women's March which aims to head towards the White House, told NPR the group was relieved to finally get the permit from DC police. She said participants hope to send Trump a message that they do not agree with the stances he took during his campaign.

"I can only hope that this massive gathering reminds him that now he's president and he represents all of us," claimed Chakraborty.

According to NPR, Bikers for Trump, which expects 5,000 motorcyclists in celebrating the president-elect's victory, are the only group to have received the green light from the Inaugural Committee to use a small park along the inaugural parade route.