The so-called "Red Flags Rules" are aimed at spotting possible indicators of identity theft such as suspicious documents, unusual activity in a bank account and alerts from credit bureaus.

Last week, Southwest Airlines announced a deal to sell travel to Mexico in 2010 with partner Volaris, a well-financed Mexican carrier that is 2 years old. Southwest has already said it would team with WestJet to offer U.S.-Canada travel by late 2009.