Territorial waters supply rules deem GST location and place of supply to the nearest coastal State or Union territory. Section 9 deems supplies connected with territorial waters to be linked to the adjacent coastal State or Union territory for GST purposes. Where the supplier's location is in territorial waters, or where the place of supply is in territorial waters, the relevant location is treated as the nearest coastal State or Union territory based on the appropriate baseline. The provision operates notwithstanding anything contained in the Act and establishes the territorial basis for determining the nature of supply in such cases.