White House officials are looking at a range of options from simply proposing a set of "principles" or proposing to cap greenhouse gas emissions from power plants. In the past the White House has preferred to look at voluntary measures to reduce global warming.
The Senate is expected to begin debate in June on legislation that would allow polluters to purchase emission permits instead of making actual reductions. It is designed to cut emissions 70 percent by mid-century. The House also is planning to draft climate legislation soon. The administration is facing growing pressure to regulate carbon dioxide under the existing federal clean air law. The Environmental Protection Agency has been told by the Supreme Court that carbon dioxide, the leading greenhouse gas, is a pollutant and must be regulated if the EPA determines it is a danger to health and welfare.