The U.S. Justice Department said it is ready to appeal a ruling that eliminated the nation's mask mandate for plane and train travel if necessary, even after some argued the best way to preserve the government’s authority was to let the case die.

Monday’s federal court ruling scuttling the requirement has posed a difficult legal and political calculus for the department and for U.S. President Joe Biden, with airlines opposed to the mandate along with widespread public exhaustion with masking. Late Tuesday, the U.S. said it would appeal the ruling if the Centers for Disease Control and Prevention decides that masks should remain in place past the current assessment period, which is due to expire May 3.

The government’s top priority is to protect what power it has left to enact a mandate months down the road if there’s another surge in COVID-19 cases, administration officials said earlier, speaking on the condition of anonymity as deliberations continued.