In advance of a political showdown in the state Legislature, Gov. Jerry Brown’s administration made its first formal effort Tuesday to extend the life of the program central to California’s bid to combat climate change.

The California Air Resources Board, which is controlled by the governor, released a plan that would continue the state’s cap-and-trade program to cut carbon emissions beyond 2020, the date when the program currently expires. Cap and trade functions by forcing companies to buy permits in order to pollute, providing a financial incentive for power plants, oil refineries, manufacturers and other businesses to reduce their emissions.