A senior White House official responded strongly to the letter Senate majority leader Mitch McConnell (R) of Kentucky sent Thursday to all state governors urging them to defy rules drafted by the Obama Administration to curb carbon pollution from coal fired power plants.

In his letter, Senator McConnell, who represents a major coal producing state, laid out a legal rationale for the governors to refuse to submit compliance plans to the Environmental Protection Agency. He argued that the use of the Clean Air Act to change power plant regulations was unconstitutional.

“Declining to go along with the administration’s legally dubious plan will give the other two branches of government time to address the proposal and will not put your state at risk in the interim,” the majority leader wrote. “It will provide time for the courts to rule on whether the EPA’s proposed rule is legal, and it will give Congress a chance to address numerous concerns surrounding this latest power grab by the EPA.”

Brian Deese, a senior adviser to President Obama whose portfolio includes climate conservation and energy policy, fired back at McConnell’s effort during a Monitor-hosted breakfast for reporters on Friday.

“What you have is a Republican leader in Mitch McConnell who is going way outside the bounds of the position that he was elected to,” Mr. Deese said. “We all would be better served if he and others spent less time trying to lecture states about what they should be doing ... and more time actually trying to get some constructive things done in Congress, like for example, we could confirm a highly qualified attorney general nominee who has been sitting out there for more than 130 days.”

The power plant emission rules are just once part of a regulatory push to reduce greenhouse gas emissions which Deese called “a very aggressive agenda.” On Thursday the president signed an executive order to cut the federal government’s emissions of the heat trapping gases that cause global warming by 40 percent over 2008 levels in the next decade. On Friday, the administration announced proposed rules regulating the use of hydraulic fracturing to recover oil and gas on federal lands. Fracking is a process in which water, chemicals, and sand are injected underground to free oil or gas from rock.

In the final quarter of Mr. Obama’s time in office, there will continue to be a focus on items he can implement by executive action without needing to wait for Congress. Dealing with stagnating middle class wages will be a key priority, said Jeffrey Zients, director of the National Economic Council, who also spoke at Friday’s breakfast.

“We will continue to execute on the executive actions we have already rolled out and do new executive actions,” Mr. Zients said.