Countries will have to track and monitor different types of plastic waste outside its borders, according to updates to the agreement linked to the Basel Convention and signed by 187 countries.
"It's sending a very strong political signal to the rest of the world -- to the private sector, to the consumer market -- that we need to do something," Rolph Payet of the United Nations Environment Program told The Associated Press. "Countries have decided to do something which will translate into real action on the ground."
Even countries that did not sign it could be affected.
"(The changes) would prevent the U.S. from sending -- it would only allow the U.S. to export plastic waste that is already sorted, cleaned and ready for recycling," David Azoulay of the Center for International Environmental Law (CIEL) told Reuters. "Which is exactly the type of waste they don't send around because it has value."
The United States, Germany and Japan shipped over 1 billion pounds of plastic waste last year, Reuters reported. China stopped processing other countries' plastic waste in 2017, leading to more of it being disposed in southeast Asia, where it is more difficult to manage and dispose, Reuters reported.
UN environmental officials said there is more than 100 million tons of plastic waste in the world's waterways with more than 8 million tons added each year.
The Associated Press contributed to this report.