2.1.9 Parties having accepted responsibility to provide search and rescue services for a specified area shall use search and rescue units and other available facilities for providing assistance to a person who is, or appears to be, in distress at sea.

2.1.10 Parties shall ensure that assistance be provided to any person in distress at sea. They shall do regardless of the nationality or status of such a person or the circumstances in which that person is found.

SAR Convention (1979) : http://www.imo.org/en/KnowledgeCentre/IndexofIMOResolutions/Maritime-Safety-Committee-(MSC)/Documents/MSC.70(69).pdf