The Canadian government on Thursday set a date of January 2020 to begin enforcing methane emissions reduction requirements on the oil and gas industry.

The target surfaced in the formal Canada Gazette publication of planned regulations. It’s the latest step toward carrying out an environmental promise dating back to the current Liberal government’s 2015 election campaign.

No change is made to the pledge to try for reductions of 40-45% below 2012 levels as of 2025, or to previously posted regulation drafts. The plan continues to schedule gradual implementation of emissions controls by implementing annual rule changes.

Leaks, venting and equipment exhaust are all covered by the highly technical scheme. The cleanup is forecast to cost the industry a total of C$3.9 billion ($3.1 billion) in installments averaging C$230 million ($184 million) over an extended implementation period through 2035. Government economists predict captured methane emissions will help pay the bills by generating about C$1 billion in gas sales.

The final shape of the national methane cleanup remains unsettled because the fossil fuel producing provinces — especially Alberta, British Columbia (BC) and Saskatchewan — have primary constitutional responsibility for resource development.

Federal government explanations of the newly published regulations explain that they are intended as a “backstop” to ensure the provinces take action.

“Provinces and territories can put in place methane regulations that make sense, given their circumstances, provided they can clearly demonstrate emission reductions equivalent to the federal measures,” the notice said. “Environment and Climate Change Canada is open to discussing the establishment of equivalency agreements, under the Canadian Environmental Protection Act, 1999, with interested provinces.”

The regulation publication was unveiled with considerable political emphasis at an Ottawa news conference with Environment Minister Catherine McKenna and Natural Resources Minister Jim Carr.

The event garnered political favor in the United States, where the Environmental Defense Fund circulated a statement applauding Canada for setting an example that should be followed by all fossil fuel producing countries.

The Canadian ministers, meanwhile, also released extensive reviews explaining previously announced marine safety measures to prevent spills by increased oil tanker traffic. The actions were devised in 2016 when the federal cabinet approved Kinder Morgan Canada Ltd.’s expansion project for the Trans Mountain Pipeline from Alberta to the Pacific coast of BC, where environmental, provincial and local government, and native opposition continues to stall construction.