Section 33. Contracts for supplies and commodities needed in the administration of assistance

The department may
    (a)   make agreements for  supplies  and  commodities  needed  in  the
  administration  of  assistance and care, under which local welfare units
  may, subject to the approval of the department, purchase  such  supplies
  and commodities; and
    (b)  in accordance with requisitions duly approved by the commissioner
  of general services, purchase as the agent of local welfare units and on
  their  request,  supplies or commodities needed in the administration of
  assistance and care and  make  payments  therefor  after  making  proper
  deductions  from  state  reimbursements  due the local units which avail
  themselves of the provisions of this subdivision.