The term “city” means (A) any unit of general local government which is classified as a municipality by the United States Bureau of the Census or (B) any other unit of general local government which is a town or township and which, in the determination of the Secretary, (i) possesses powers and performs functions comparable to these associated with municipalities, (ii) is closely settled, and (iii) contains within its boundaries no incorporated places as defined by the United States Bureau of the Census which have not entered into cooperation agreements with such town or township to undertake or to assist in the undertaking of essential community development and housing assistance activities.