By JON GAMBRELL
DUBAI, United Arab Emirates (AP) — The U.S. Navy has held a joint drone drill with the United Kingdom in the Persian Gulf. The drill Friday tested the same unmanned surveillance ships that Iran twice has seized in recent months in the Middle East. The exercise comes as the U.S. Navy separately told commercial shippers in the wider region that it would continue using drones in the Middle East and warned against interfering with their operations. The drone drill also comes as tensions between the U.S. and Iran on the seas remain high amid stalled negotiations over its tattered nuclear deal with world powers and as protests sweep the Islamic Republic.