The teachers and principals unions are warning of possible staffing shortages this Monday if Mayor Bill de Blasio's vaccine mandate for Department of Education employees goes into effect.

Not enough teachers and a shortage of school lunches are just some of the concerns being brought to the table by the teachers union looking to pause the city's vaccine mandate for all public-school teachers.

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Both the teachers and principals unions are now calling on the city to delay the implementation of the vaccine mandate that will take effect this Monday, Sept. 27 at midnight.

De Blasio has made it clear that teachers and other DOE employees who have not gotten a least one dose come Tuesday morning will not be paid.

The city says it has substitute teachers on standby to fill those roles in case of staff shortages.

The unions representing principals and teachers held a meeting Friday morning to voice their concerns about what could happen come Tuesday morning. They say some of the bigger schools have between 30 to 100 DOE employees who are on the non-compliance list.

Another issue is safety. They say school safety officers are being deployed, which will leave one officer per school.

The unions are asking for City Hall to delay the vaccine mandate and come up with a concrete plan to ensure that all public schools will be safely staffed.

The teachers union says about 6,000 of its members are not vaccinated and that's enough to impact schools that are not prepared for staff shortages.