24 C.F.R. § 570.906
In reviewing the performance of an urban county, HUD will hold the county accountable for the actions or failures to act of any of the units of general local government participating in the urban county. Where the Department finds that a participating unit of government has failed to cooperate with the county to undertake or assist in undertaking an essential community development or assisted housing activity and that such failure results, or is likely to result, in a failure of the urban county to meet any requirement of the program or other applicable laws, the Department may prohibit the county's use of funds made available under this part for that unit of government. HUD will also consider any such failure to cooperate in its review of a future cooperation agreement between the county and such included unit of government described at § 570.307(b)(2) .
24 C.F.R. §570.906