The Obama administration is proposing to cut methane emissions from U.S. oil and gas production by nearly half over the next decade in an unprecedented step to curb climate change. 

The administration's target is to cut methane from oil and gas drilling by 40 to 45 percent by 2025, compared to 2012 levels. The move was not unexpected -- officials set the same goal in a preliminary blueprint in January. Still, by moving forward with the official proposal, President Barack Obama is adding to a list of energy regulations that have drawn applause from environmentalists and ire from energy advocates. 

To meet the goal, the administration was expected to issue the first U.S. regulations cutting emissions from new natural gas wells, along with updated standards for drilling to reduce leakage from wells on public lands. It's unclear how much those regulations will cost the energy industry to comply. 

The Environmental Protection Agency scheduled a noon announcement to unveil the proposal. 

"Today, through our cost-effective proposed standards, we are underscoring our commitment to reducing the pollution fueling climate change and protecting public health while supporting responsible energy development, transparency and accountability," EPA Administrator Gina McCarthy said in a prepared statement. 

The administration is expected to finalize the rules next year shortly before Obama leaves office. 

Methane, the key component of natural gas, tends to leak during oil and gas production. Although it makes up just a sliver of greenhouse gas emissions in the United States, it is far more powerful than the more prevalent gas carbon dioxide at trapping heat in the atmosphere. That makes methane a top target for environmentalists concerned about global warming. 

With his presidency drawing to a close, Obama has been in a rush to propose and then finalize sweeping regulations targeting greenhouse gases blamed for global warming. 

The methane rule, follows a landmark regulation Obama finalized earlier this month to cut carbon dioxide emissions from coal-fired power plants by 32 percent. The plan, a key element of Obama's climate change strategy, drew immediate legal challenges from power companies and Republican-led states. 

In total, Obama has set a goal to cut overall U.S. emissions by 26 percent to 28 percent over the next decade, as he seeks to leave a legacy of using the full range of his executive power to fight climate change and encourage other countries to do the same. 

Earlier this year, the administration said it only intends at first to regulate emissions from new or modified natural gas wells, meaning thousands of existing wells won't have to comply. 

Environmentalists say that the ambitious goals announced under the proposed rule would be difficult to meet without targeting existing wells. 

David Doniger, climate policy director for the Natural Resources Defense Council, an environmental group, called the new rule "a good start." But Doniger said, "EPA needs to follow up by setting methane leakage standards for existing oil and gas operations nationwide."