Rotting garbage piled up in many parts of the capital after the giant rubbish tip collapsed in April, crushing dozens of homes and killing 32 people.
Many blamed the haphazard use of plastic, which was also cited in flash flooding in the capital after storm water drains became clogged.
In response, President Maithripala Sirisena banned the sale of plastic bags, cups and plates, as well as the burning of refuse containing plastic.
“Any person who fails to comply with the regulations… shall be liable to an offence and punishable under the National Environmental Act,” the president said.
Offenders could be fined 10,000 rupees ($66) and jailed for up to two years.
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