New Jersey is the only state sticking to indoor mask mandates for fully vaccinated people following the CDC's more relaxed guidelines. 'We're not ready yet,' its governor said.

• The CDC said Thursday that fully vaccinated Americans don't need a mask in most places.
• Every state other than New Jersey has relaxed its indoor mask guidance, or said it soon would.
• Gov. Phil Murphy said that the state needed "a couple more weeks" to ensure new rules were safe.

New Jersey is the only state with no plans to update its indoor mask mandate to align with new federal guidance on fully vaccinated people.

The Centers for Disease Control and Prevention (CDC) recommended Thursday that fully vaccinated Americans no longer need a mask in most indoor and outdoor settings. The majority of states with mask-wearing mandates lifted restrictions immediately, while others, including New York, gave a date for more relaxed rules.

New Jersey Gov. Phil Murphy told CNN on Monday: "We're not necessarily against it. We're not ready yet."

Murphy said that New Jersey needed "a couple more weeks" to ensure that it was safe to update its indoor mask mandate.

"If we could save one more life by waiting a couple of weeks longer. I'll sign up for that," Murphy said.

Murphy also suggested it was unfair to ask retail workers to judge whether people were fully vaccinated or not.

He did, however, announce that the state was lifting its outdoor mask mandate for everybody. He also said people didn't need to isolate on return to New Jersey after travel, and that schools would restart in-person teaching in the fall.

In the past week, New Jersey has recorded more than 3,000 new coronavirus cases, down from a peak of more than 42,000 in January. In the same period, 165 people died from COVID-19 in the state, down from a weekly peak of more than 2,400 in December, according to Johns Hopkins University.

Murphy said that the virus was more lethal indoors, and that the mask requirement inside had been "hugely helpful".

"Twice before we thought we had this thing [coronavirus] on the run and it came back and clobbered us again," he said.

The majority of people in New Jersey aren't fully vaccinated. Murphy said that this was another factor in his decision-making. About 40% of people in the state are fully vaccinated, according to Johns Hopkins University. "We gotta bring the vaccine to the people," Murphy said.

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State Sen. Michael Testa, a Republican, said it was "unbelievable" that Murphy was doubling down on the mask mandate.

"Instead of following the science here in New Jersey, we have a governor who continues to restrict personal freedoms to cater to the irrational fears of a timid liberal constituency," he said.

Others supported Murphy's decision.

Marc Perrone, international president of the United Food and Commercial Workers International Union, said Sunday that while vaccinations were helping us slow the spread of COVID-19, the pandemic was far from over.

"We cannot let our guard down," Perrone said.