NASHVILLE, Tenn. (March 5, 2013)--Carly Rae Jepsen has cancelled her performance at the Boy Scouts of America Jamboree this summer because of the organization’s exclusion of gays.

Jepsen said Tuesday on Twitter that "as an artist who believes in equality for all people" she's pulling out of the jamboree, which is in July in West Virginia.

The event, held once every four years, is expected to draw more than 45,000.

The rock band Train also warned that it won't appear unless the organization stops barring participation by gay scouts or adult leaders.

Train said on its website that it was unaware of the policy before agreeing to perform and that the organization must now make "the right decision."

BSA director of publicity Deron Smith said the BSA appreciates "everyone's right to express an opinion" and remains focused on staging a great jamboree.