45 CFR 234.75: Rent payments to public housing agencies.

At the option of a State, if its plan approved under title I, X, XIV, or XVI of the Social Security Act so provides, Federal financial participation under such title is available in rent payments made directly to a public housing agency on behalf of a recipient or a group or groups of recipients of OAA, AB, APTD, or AABD. Such Federal financial participation is available in rent payments only to the extent that they do not exceed the amount included for rent under the State's standard of assistance or the amount of rent due under applicable law, whichever is less.