Ben Carson said Sunday that he was unsure what exactly would happen to the passengers on the stranded Grand Princess cruise ship after it docks in Oakland, Calif., on Monday. The ship, en route from Hawaii to Mexico, remains stuck at sea after being refused permission to dock in California.

The secretary of the U.S. Department of Housing and Urban Development was speaking with ABC News’ George Stephanopoulos about the Trump administration’s response to the novel coronavirus, and appeared reluctant to discuss the issue. Twenty-one people aboard the Grand Princess have reportedly tested positive for COVID-19 — 19 of them crew members.

“ ‘We shouldn’t have 16 people saying what the plan is, particularly when it hasn’t been fully formulated.’ ” — Ben Carson, HUD

“The cruise-ship personnel and, as you now, the vice president met with the CEOs of the major cruise-ship companies yesterday, and they are coming up with a plan within 72 hours of that meeting,” Carson said in the interview with Stephanopoulos on ABC DIS, -0.76% .

Stephanopoulos reminded Carson that the Princess Cruises was docking within 24 hours. Carson responded, “The plan will be in place by that time, but I don’t want to preview the plan right now.” The ship was refused permission to dock on Thursday; it was then expected to dock Sunday.

Carson said the cruise ship, which has around 3,500 passengers on board, confirmed that no plan was in place as yet. “I think it all needs to come from a solitary source. We shouldn’t have 16 people saying what the plan is, particularly when it hasn’t been fully formulated.”

View the interview here:

President Trump on Friday said he personally would prefer the passengers to remain on board. “I would rather have the people stay ... 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.”

Another Carnival Corp. CCL, -5.81% cruise ship, the Diamond Princess, was quarantined off the coast of Japan last month for two weeks. Dozens of people tested positive for the virus, and a total of seven passengers from that ship have died, Japanese public broadcaster NHK said Saturday.

Travel on cruise ships is particularly popular among families and the elderly. Younger children with strong immune systems have the lowest fatality rate from COVID-19, but those with stronger immune systems may be prone to spreading the virus to more vulnerable passengers.

Also see:Ben Carson urges people to be calm about coronavirus: ‘This virus is like other viruses’

The Grand Princess cruise ship sits off the coast of San Francisco as it takes on supplies. Getty Images

Also see:Gov. Cuomo declares state of emergency in New York over coronavirus

Worldwide, there were 110,588 COVID-19 cases and 3,841 deaths as of Monday morning, according to the Johns Hopkins Whiting School of Engineering’s Center for Systems Science and Engineering. In the U.S., 22 people have died, and there are approximately 564 confirmed cases.

Carnival Corp.’s stock is down sharply in 2020, as are other cruise lines. Royal Caribbean RCL, -4.91% is down 51% over the same period, while Norwegian NCL, +5.55% has fallen 53.6%. Carnival’s year-to-date decline is just shy of 47%.

The Dow Jones Industrial Index DJIA, -0.91% is down 9.4% since the beginning of January, and the Standard & Poor’s 500 Index SPX, -1.21% has fallen 8% over the same period. Princess Cruises and Carnival did not respond to requests for comment from MarketWatch.

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