Christina Aguilera, Sienna Miller Participating in Red Nose Day NBC Telethon: See Photos!

Christina Aguilera
Christina Aguilera is among the celebrities lending their support for Red Nose Day 2015. Trae Patton/NBC

Christina Aguilera and Sienna Miller are getting silly for a good cause. The Voice coach and American Sniper actress are among the first stars pledging their support and participation in NBC's upcoming live telethon for Red Nose Day, the network announced March 18. To celebrate their involvement, Aguilera, 34, and Miller, 33, each posed wearing the charity initiative’s signature red nose.

Airing May 21 in an event originating from New York City, the Peacock network's three-hour live telethon will feature standup and sketch comedy bits, musical performances, and celebrity guests. According to Variety, Mad Men's Jon Hamm is scheduled to lend a hand in the broadcast.

Long familiar with Red Nose Day from its 30 years airing in the UK, Miller is thrilled the U.S. is bringing attention to the cause, which aims to raise money and awareness for those stricken by extreme poverty.

Sienna Miller Red Nose Day
Sienna Miller is participating in NBC's Red Nose Day telethon. Giles Park/NBC

"Red Nose Day is almost like a national holiday in the UK It's a day of real excitement as everyone looks forward to it and the entire country gets involved in some way," Miller tells Us Weekly in a statement. "I'm thrilled it’s coming to the U.S.!" Through its massive fundraising efforts, the UK Red Nose Day initiative has raised more than $1 billion to date.

NBC has earmarked 12 charities to receive funds raised on Red Nose Day: Boys & Girls Clubs of America; charity: water; Children's Health Fund; Feeding America; Gavi, The Vaccine Alliance; the Global Fund; Lift; National Council of La Raza; National Urban League; Oxfam America; Save the Children and United Way.

NBC's Red Nose Day special airs May 21 from 8-11 p.m. EST.

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