Singapore has a message for shipping companies considering cheating on rules starting next year to combat pollution to save a few dollars on their fuel bills: don't.

Captains and owners of vessels that burn overly sulfurous fuel in the Asian country's territorial waters could face as long as two years in prison from the start of 2020, according to the Maritime and Port Authority of Singapore. If enforced, such a penalty would probably be among the strongest deterrents yet to dodging regulations that are supposed to cut emissions of a pollutant blamed for asthma and acid rain.