How do I make sure that an employee and supervisor belong to the same company?

I have an employees table and one column in the employees table is
"supervisor_id" which is an FK to the id column.

I have employees from numerous companies all in the same table.  I have
a column called company_id that indicates the company.

I want to make sure that an employee chooses a supervisor from the same
company.  I have a column called company_ID.  How do I make sure that
the employee company ID matches the supervisor's company ID?

Do I need to use a trigger or is there a way I can do this with foreign
keys?

TIA

Matt