If you are a foreigner in Thailand and requesting to work in a public sector organization, state enterprise, or other public agency, you must submit an application with the following requirements:

1. You must hold a Non-Immigrant Visa;
2. Your request must be approved and supported by the agency or organization. 

Required documents:

1. TM.7 form;
2. Copy of the applicant's passport;
3. Copy of work permit;
4. Confirmation letter from a public sector organization, state enterprise, or other relevant public agency;
5. Proof of a public agency (if any).

Source: Immigration Office

Tel. 1178 or 0 2572 8500