NEW YORK — Model and human rights activist Heather Mills celebrated her new role as the face for INC International Concepts’ spring campaign here Monday night.

“I wouldn’t do it unless we were helping a charity — I’m not a big designer kind of gal unless it’s 75 percent off,” said INC-clad Mills, at the campaign launch party held in the former Moomba space, accompanied by fiancee Paul McCartney, who greeted fans warmly, signing autographs and Beatles albums.

Wearing what she described as “hipster black pants” and a sleeveless black top, Mills said she shuns pricey designer labels and lauded the affordably priced INC brand, sold throughout the Federated Department Stores various chains. “You don’t have to spend a fortune on clothes to look great. It’s like you need someone else’s name more than you need your own.”

Mills’ role with the campaign marks the 34-year-old’s first return to modeling in five years, a career that was thrown a challenge after she lost her left leg in a motorcycle accident in 1993.

INC has devoted its spring campaign to raising awareness for Adopt-A-Minefield, a United Nations program committed to resolving the global land-mine crisis — an issue that is dear to Mills. Mills became involved in the cause after traveling through the former Yugoslavia in her early twenties. She eventually moved there, using money earned while modeling to help refugees.

During the month of February, a percentage of proceeds from sales will be donated to the program on behalf of Mills.

Nancy Slavin, group vice president for international marketing at Federated said the company knew Mills should represent INC after meeting her at a luncheon Sept. 10.

“We always look for women who inspire us and we met her and loved her cause,” she said. “We want to create an emotional connection with our consumer …and what [Heather] wants to be known as is someone that champions an important cause.”

To educate consumers about the land-mine crisis, Mills will be making personal appearances at events across the U.S. The first of these scheduled events is at 12:30 p.m. Friday at Macy’s Herald Square.