In a letter to Lisa P. Jackson, the E.P.A. administration, the head of the White House office of regulatory affairs, Cass Sunstein, said that the president was rejecting her proposal to tighten the standard.
"He has made it clear he does not support finalizing the rule at this time," Mr. Sunstein said.
He said that changing the rule now would create uncertainty for business and local government. He also said there was no compelling reason to rewrite the ozone standard in advance of the scheduled reconsideration in 2013, a key demand of business interests.
Mr. Sunstein told Ms. Jackson that since the rule is due for reconsideration in 2013, an earlier review would promote confusion and uncertainty.
"In this light," he wrote, "issuing a final rule in late 2011 would be problematic in view of the fact that a new assessment, and potentially new standards, will be developed in the relatively near future."From the NYT
update: another from the NYT: Stung by Obama, Environmentalists Weigh Options.