A US passport is required in order to go on all international air trips. This does not affect your ability to book and pay your deposit for the trip at this time. Just be aware that you are responsible for obtaining a valid passport prior to departure date.
Please either apply for a new passport or renew your passport if it expires 6 months after your return date for this trip. It takes 4-6 weeks to receive your passport in the mail. Due to Covid-19 processing times can take longer than normal.
Please visit travel.state.gov to begin the process.