From the New York Post:

Lisa Jackson, the Environmental Protection Agency administrator, was on the verge of quitting two weeks ago after President Obama rejected her centerpiece proposal for strict new air-pollution regulations, the Post has learned.

Jackson told intimates she had been convinced Obama would back her up despite aggressive lobbying from Capitol Hill Republicans and business interests.

But on Sept. 1, she learned her support in the West Wing had crumbled during two meetings -- one with Chief of Staff Bill Daley and another with the president.

In the face of a weak economy, bad poll numbers and bleak employment figures, Obama made it clear that “we just don’t need this fight right now,” according to an administration source.

A day later, the administration announced it was abandoning the proposal for the tougher emissions rules, which would have cut the amount of ozone that can be spewed into the air.

The White House said that it would revisit the issue in 2013, but that, for now, the changes to the Clean Air Act would have burdened businesses and local governments with costs to contain and monitor air pollution.

For more, see: EPA chief on verge of quitting after Obama rejected pollution proposal