Leona Lewis and Ashanti are among the confirmed performed slated to take the stage for NBC's Christmas in Rockefeller Center special airing Wednesday, Dec. 4 at 8 p.m. ET.

They join previously announced performers Audra McDonald, Alauren Alaina, Mary J. Blige, Toni Braxton, Mariah Carey, Kelly Clarkson, Kenny 'Babyface' Edmonds, Goo Goo Dolls, Ariana Grande, Jewel and The Rockettes.

NBC will celebrate the lighting of the world's most famous Christmas tree with a live broadcast from Rockefeller Center in New York City from 8-9 p.m. ET. Ashanti and Alaina will perform only in the 7-8 p.m. ET hour airing on select NBC stations.

The 81st annual holiday event will feature a 76-foot Norway Spruce that is 47 feet in diameter and weighs approximately 12 tons. The tree is estimated to be about 75 years old. More than 45,000 energy-efficient multi-colored LED lights will be strung to decorate the tree, topped with a 9 ½ foot wide LED-lit Swarovski crystal star.

After the lighting ceremony, the tree will remain lit between 5:30 a.m. to 11:30 p.m. and for all 24 hours on Christmas Day. The last day to view the Norway Spruce will be Jan. 7, 2014. The tree will then be milled into lumber that will be donated to Habitat for Humanity.

Attendance for the lighting ceremony is free, but it is recommended to get there easy since thousand of people gather each year to watch the event. The pre-taped performances are listed below, with tickets already sold out for them all:

Ariana Grande- 11/26/13
Kelly Clarkson - 11/26/13
Mariah Carey, Toni Braxton, Babyface - 12/3/13

NBC-TV televised the tree lighting for the first time in 1951 on The Kate Smith Show and as part of the nationwide Howdy Doody television show from 1953-55.