As you mentioned ,You are going supplying services to government office, it therefore is obvious that you had under gone bidding process against the tender submitted. I Know that any government office would ask for epf and basic documents and registrations., In such circumstance irrespective of number of employees, you must voluntarily register with epf andesic and start contributing.
As a matter of fact no government office will be able to release your bill payments unless they audit your compliance every month.