NEW YORK, Oct 5 (Reuters) - Discount carrier JetBlue Airways Corp. faces opposition from UAL Corp.'s United Airlines in its efforts to gain landing rights to Chicago's congested O'Hare International Airport.

United argues that JetBlue's request, which was filed with the Federal Aviation Authority last week, doesn't follow proper procedures and should be denied, according to a filing on Wednesday with the FAA.

"JetBlue must operate in accordance with the regulatory rules of the road, just as all other carriers must do. Because its current request ignores those rules, it must be denied," United says in the filing.

New York-based JetBlue doesn't currently serve the Chicago area, but is keen to start up service to the United and American Airlines (AMR.N: Quote, Profile, Research) hub. The traffic at O'Hare is closely regulated, and few low-cost carriers have service there.

"Obviously, it's a very important market for us," said JetBlue spokeswoman Jenny Dervin. The carrier is in a position to start up service within 60 days of getting approval, she said.