SEATTLE (AP) — Washington state's largest industrial polluters would be required to reduce carbon emissions gradually over time under a proposed rule.

The measure released Wednesday is a key piece in Gov. Jay Inslee's efforts to tackle climate change and reflects other efforts in California and the Northeast.

After failing to win passage of a plan to charge a fee for emissions, Inslee directed the state Department of Ecology to limit greenhouse gas emissions under its existing authority.

Under the rule, large emitters would be required to reduce carbon emissions by an average of 1.7 percent annually.

The rule would initially apply to about two dozen oil refineries, power plants and others that release at least 100,000 metric tons of carbon a year. More facilities would likely be covered by the rule as the threshold is lowered over time.

It's the state's second attempt at an emissions rule.