LOS ANGELES — A United Nations agency that regulates the international shipping industry has adopted a plan to dramatically reduce air pollution coming from ships off the U.S. and Canadian coasts.

The decision today by the International Maritime Organization will require all oceangoing ships, including oil tankers, cargo vessels and cruise ships, to use cleaner-burning fuel within 230 miles of the coast. The rule is supported by U.S. agencies and will take effect in 2015.

The U.S. Environmental Protection Agency says the new regulation will cut sulfur oxide emissions and soot pollution from large ships by as much as 85 percent. The EPA says much of the country will see improved air quality.

California is at least one state that mandates ships within 24 miles of the coast to burn cleaner fuel.