US deaths from the new coronavirus could reach 200,000 with millions of cases, the government's top infectious diseases expert warned on Sunday as New York, New Orleans and other major cities warned they would soon run out of medical supplies, Reuters reports.

Dr Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, estimated in an interview with CNN that the pandemic could cause between 100,000 and 200,000 deaths in the United States.

A shortage of ventilators in several major cities worsened as the US death count crossed 2,100 on Saturday, more than double the level from two days ago. The United States has now recorded more than 123,000 cases of COVID-19, the disease caused by the virus, the most of any country in the world.