During a tour of the Center for Disease Control on March 6, 2020, Trump said he preferred to prevent a cruise ship with confirmed COVID-19 cases from docking for fear that the official number of US cases would increase.

They would like to have the people come off. I’d rather have the people stay [on the ship]. But I’d go with them. I told them to make the final decision. I would rather – because I like the numbers being where they are. I don’t need to have the numbers double because of one ship that wasn’t our fault.

The US had 319 confirmed cases and 15 deaths.

Trump later called coronavirus testing “overrated,” and said that halting testing would mean that there would be no more cases. Trump spent the early months of the coronavirus pandemic dismissing concerns about the growing crisis.

Business Insider – Trump said he wants to keep Grand Princess cruise passengers on the ship so that US coronavirus numbers don’t ‘double.’ That strategy failed in Japan.
Fox News – Trump wants cruise ship passengers to stay at sea, but leaves decision up to Pence
Market Watch – Trump on allowing Grand Princess cruise passengers to disembark: ‘I’d rather have them stay on, personally’
Worldometer – Coronavirus, United States