Singer Carrie Underwood has gone to war with politicians in her adopted Tennessee over plans to ban animal rights activists from capturing undercover video footage at farms. The vegetarian has gone public with her opposition to a new "ag gag" bill, which was introduced in the state last week (ends19Apr13). The ordinance prohibits undercover filming of farms, so staffers lacking compassion can hide cruelty, food and labour safety violations. Underwood took to Twitter.com to let followers know where she stood, posting: "Shame on TN lawmakers for passing the Ag Gag bill. If Gov. Bill Haslam signs this, he needs to expect me at his front door. Who's with me?" And when Republican state representative Andy Holt responded to her criticism, telling the local NBC TV affiliate, "I would say that if Carrie Underwood will stick to singing, I'll stick to lawmaking," the furious singer took aim at him, too. She tweeted: "I should stick to singing? Wow... sorry, I'm just a tax paying citizen (sic) concerned for the safety of my family."