U.S. nationals, including dual nationals, must use a U.S. passport to enter and leave the United States. Dual nationals may also be required by the foreign country to use its passport to enter and leave that country.
Use of the foreign passport to travel to or from a country other than the United States is not inconsistent with U.S. law.
Americans should expect delays when applying for nonemergency passport or citizenship services, and that operating hours vary significantly between embassies, as each is facing different Covid-19 restrictions. Appointments are backlogged. The State Department prohibits bootlegging appointments (stockpiling appointments in order to sell them at exorbitant prices).
Emergency passport services are available through local embassies. For example, the Israeli consulate.
Temporary help through 2021:
To help, the U.S. Customs and Border Protection is accepting certain recently expired U.S. passports for return travel.
An airport connection en route to the U.S. can be made.
Certain criteria apply so U.S. citizens must confirm their eligibility for traveling on an expired passport at COVID-19 Traveler Information prior to finalizing travel arrangements.
U.S. citizens who wish to return to the United States that proof of a negative COVID-19 test result, taken within 72 hours of their flight’s departure, is required for air travel to the United States.