U.S. airlines are suing to block the Biden administration from requiring greater transparency over fees that the carriers charge their passengers, saying that a new rule would confuse consumers by giving them too much information during the ticket-buying process.

The U.S. Transportation Department said Monday it will vigorously defend the ruleagainst what it called “hidden junk fees.”

American, Delta, United and three other carriers, along with their industry trade group, sued the Transportation Department in a federal appeals court on Friday, asking the court to overturn the rule.