SAN FRANCISCO (CBS SF) — San Francisco Mayor London Breed expanded the city’s COVID-19 vaccination mandate Friday to include not only municipal employees, but also all city contractors who work with them.

The mayoral order requires the contractor work crews to be fully vaccinated by December 31st.

READ MORE: Flash Flood Watches Issued As Storm Aims at Fire-Scarred Northern California

Currently, the city’s municipal worker mandate requires full vaccination by November 1, with earlier deadlines for those who work in high-risk facilities like jails, hospitals and homeless shelters. If an employee does not comply, they could face termination.

“Our vaccine mandate for city employees has always been about protecting the public we serve and protecting our workforce,” Breed said. “By extending the mandate to contractors who work alongside our city workers, we are continuing to do everything we can to keep our city workforce strong and healthy.”

READ MORE: Amid the Capitol Riot, Facebook Faced Its Own Insurrection

Under the order, the city administrator’s office will be tasked with issuing processes and procedures to implement the vaccine mandate and provide guidance regarding the policy.

“Our workforce is our most valuable asset,” said City Administrator Carmen Chu. “We’ve leaned upon our workers to continue delivering critical public services throughout the pandemic because that’s what we all signed up to do…Vaccine requirements to those who work beside us is a natural extension of our commitment to protect our workforce and the public we serve.”

MORE NEWS: US Rowing Accepts Resignation of Longtime Men's Coach Mike Teti

San Francisco’s city workforce has one of these highest vaccination rates of any city in the country. Currently, over 94% of all municipal workers are vaccinated with just over 2,000 employees out of 35,000 registered as either unvaccinated or have not yet reported their status.