Los Angeles Mayor Eric Garcetti warned Thursday that city employees who don’t get vaccinated by Dec. 18 “should be prepared to lose their job.”

“The City’s employee vaccine mandate is critical to protecting the health and safety of our workforce and the Angelenos we serve,” Garcetti said in a statement. “Employees must be vaccinated by December 18, and we are putting a rigorous testing program into place in the meantime. Let me be clear: any employee who refuses to be vaccinated by this date should be prepared to lose their job.”

In August, the L.A. City Council voted to require all city employees to be fully vaccinated against COVID-19 by early October, unless they are granted an exemption for medical or religious reasons.

The rule was set to become a condition of employment on Wednesday.

But under a new plan proposed by city officials, L.A. city workers who have yet to get vaccinated or seek an exemption by Wednesday would have more time to get vaccinated — until the end of Dec. 18.

The plan would need approval from the Los Angeles City Council before it heads to Garcetti for signing.

More than 66% of city employees reported that they were fully vaccinated as of this week, according to a Los Angeles Times analysis. The number excluded data from workers at the Department of Water and Power.

Thousands have either declined to say whether they were vaccinated, or didn’t report their inoculation status, the Times reported.