The Environmental Protection Agency on Monday sent its revised greenhouse gas emissions rule for new power plants to the White House, The Hill has confirmed.

The contents of the proposed rule, which now rests in the White House Office of Management and Budget, remain sealed.

While its substance is unknown, moving the rule puts the climate plan President Obama announced last week into motion.

“EPA is moving forward on the President’s plan to address carbon pollution from power plants using the same Clean Air Act tools that have protected Americans’ health and environment from air pollution for a generation. For newly built power plants, the plan calls for EPA to issue a new proposal by September 20, 2013. As part of this process, EPA has sent the new proposal for interagency review,” the EPA told The Hill in an email.