"The White House is reviewing an Environmental Protection Agency rule on which factories and power plants will be subject to greenhouse gas regulations, according to the Office of Management and Budget website.

The measure, known as the "tailoring rule," would set emissions thresholds for big emitters of gases blamed for warming the planet. Regulated polluters could include coal-fired power plants and heavy energy users such as cement, glass and steel makers.

The fact that the White House is reviewing the rule means it could be sent back to the EPA and finalized soon. In an interview with Reuters last week, EPA Administrator Lisa Jackson said the agency may not issue the rules until May.

Jackson has said only plants that emit 75,000 tonnes per year or more of carbon dioxide are likely to be regulated under the rule in the next two years.

The EPA wants to limit U.S. Clean Air Act regulations, or "tailor" them, so they apply only to larger polluters to avoid overwhelming federal and state agencies with paperwork."

Timothy Gardner reports for Reuters April 22, 2010. [2]