(Bloomberg) -- New York City Mayor Bill de Blasio called for a private sector vaccine mandate on Monday without elaborating how the city would enforce the requirement.

He also strengthened the vaccine rules for access to indoor dining, entertainment and fitness, which currently requires people to have received at least one dose. Starting Dec. 27, people will have to be fully vaccinated to enter establishments. Kids age 5-11 will also be required to have at least one shot to enter restaurants, de Blasio said.

“All private sector employers in New York City will be covered by this vaccine mandate as of Dec. 27,” Mayor Bill de Blasio said in an interview on MSNBC Monday. He said he wants to focus on “maximizing vaccination quickly so we can get ahead of omicron and all the other challenges we’re facing.”

The city has seen a post-Thanksgiving rise in Covid-19 infections in addition to its first few cases of the omicron variant. The cases so far appear to be unrelated, according to governor Kathy Hochul, but officials have warned people to assume there is already community spread. 

“We have to assume community spread at this point,” de Blasio said. “Omicron is here.”

The city last week strengthened its recommendation for residents to wear masks indoors regardless of vaccination status and announced additional vaccine mandates on childcare workers and private school employees.

“Vaccine mandates are the one thing that really breaks through,” de Blasio said. “Let’s lean into it even more.” 

(Updates throughout)

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