NPR has reminded its employees that they are not allowed to participate in the upcoming rallies led by Jon Stewart and Stephen Colbert.

"NPR journalists may not participate in marches and rallies involving causes or issues that NPR covers, nor should they sign petitions or otherwise lend their name to such causes, or contribute money to them," Senior Vice President for News, Ellen Weiss, wrote in a memo Wednesday morning. "This restriction applies to the upcoming John [sic] Stewart and Stephen Colbert rallies."

NPR CEO Vivian Schiller forwarded the memo, sent initially to news staff, to the entire organization, telling employees that the note applied to "digital, programming/AIR, legal and communications" employees in addition to the news staff.

"However, no matter where you work at NPR you should be very mindful that you represent the organization and its news coverage in the eyes of your friends, neighbors and others," Schiller continued. "So please think twice about the message you may be sending about our objectivity before you attend a rally or post a bumper sticker or yard sign. We are all NPR."

Stewart and Colbert will host dueling rallies in Washington, DC on October 30. Stewart's "Rally to Restore Sanity" will go against Colbert's "March to Keep Fear Alive." The Huffington Post is sponsoring buses from New York to DC for the rallies.

Last year, a Fox News producer was "disciplined" after being caught on tape stoking a 9/12 protest rally crowd.