Flag states must, in accordance with the United Nations Convention on the Law Of the Sea (UNCLOS) ensure that ships under their flag comply with international regulations, often adopted by the UN's International Maritime Organization (IMO), on matters of safety, navigation, crewing etc. Part XII entail special provisions on protecting the marine environment, which includes placing special obligations on flag States to ensure compliance with international environmental legislation such as MARPOL. Failure to do so, can result in the flag state losing its jurisdiction over ships under its flag, also when these commit violations on the high seas.[4]