Washington (CNN) The group behind an effort to bring a 45-foot-tall sculpture of a naked woman to the National Mall says it is "looking to formalize litigation" after the National Park Service denied approval of the statue.

"We need a law firm willing to take on overly restrictive NPS rules that inappropriately seem to value the preservation of the perceived aesthetic of the National Mall over First Amendment activities," Natalie White, spokeswoman for Catharsis on the Mall, said in a statement . "Historical use of this public space includes free-speech demonstrations that continue to shape the character of our country."

The group has held an annual event on the National Mall that looks to marry art and activism by providing "space for arts, healing, culture, and activism to come together, mediated by radical inclusion, participation and self-expression," its website says

This year, the group had requested a permit to bring the sculpture, "R-Evolution," to the mall for the event, "to bring awareness to violence against women and the Equal Rights Amendment."

"We originally applied for this permit in December 2016 and had every reason to be hopeful that the National Park Service would allow R-Evolution to be installed," Robert "Roman" Haferd, an attorney and board member of the group, said in the statement

Haferd, who managed the permitting process, said the National Park Service "spent a month reviewing before it gave written approval of the project in September" after the group provided various plans and requirements for its installation.

The National Park Service also issued a statement on the matter, saying the request for the statue to remain up for 91 days and an accompanying temple for 119 days, "is significantly in excess of the five-day time restriction set forth in the National Mall Turf Management Guidelines."

"R-Evolution" is one of three monumental sculptures dubbed "The Bliss Project" by the creator, artist Marco Cochrane, according to Cochrane's website.

"They are intended to challenge the viewer to see past the sexual charge that has developed around the female body, which has been used for power and control, to the human being," a description of the three sculptures reads . "They are intended to de-objectify women and inspire men and women to take action to end violence against women, thus allowing both women and men to live fully and thrive."

This will be the third year of the event and will run from November 10 through November 12.