Under the proposed EU emission trading system, which is similar to cap-and-trade proposals environmentalists once tried to push in the United States, airlines from any country would have to trade credits for pollution emitted by flights to European destinations. The plan calls for airlines to reduce their emissions from 2006 levels by 3 percent by 2013 and 5 percent by 2020.
Emissions would be counted for the entire length of the flight, not just the time an airplane spends over European countries, which has drawn the ire of the U.S. airline industry.
LaHood said Wednesday he would have preferred if the EU would have worked with other countries to develop the rules instead of adopting a standard on its own.
"Be inclusive. Don't just pass a law and assume we're all just going to go along with it," LaHood said he would advise the European nations.
Lawmakers in both parties on the Senate transportation committee agreed with LaHood's assessment Wednesday.
"This is about our sovereignty," staunchly conservative South Carolina Sen. Jim DeMint (R) said.
"The European Union acted because it believes it needed to make a bold effort to reduce greenhouse gas emissions, and I understand why they did so," Committee Chairman Sen. Jay Rockefeller (D-W. Va.) said in remarks prepared for his opening statement.
"But I believe that their unilateral action is likely not sustainable by international law," he continued. "I support the goals, but I have to oppose the action."
The effort to oppose the EU's emission trading system met resistance Wednesday from Sen. John Kerry (D-Mass.), who called the objections to the rules being raised by his colleagues on the commerce and transportation panel laughable.
"I laugh at this discussion of whose airspace is whose," Kerry said. "The stuff that goes up there doesn't stay in any one airspace. We get China's fumes. We get Indiana and Massachusetts.'"
The House has passed legislation to block the EU from applying its emission trading rules to U.S. airlines, and a companion measure is being carried in the Senate by Sens. John Thune (R-S.D.) and Claire McCaskill (D-Mo.).
But Kerry said Wednesday the United States should not dismiss the EU's rule out of hand because it had been "one of the consistent foot-draggers" on reducing airline emissions.
"The Europeans are right to questions the motives of some of those who oppose their efforts ... and they're right to question whether the United States is serious about this effort, because we haven't been," Kerry said.
The New York-based Environmental Defense Fund agreed with Kerry's assessment, saying the EU's proposal for emission trading was "modest" and "reasonable."
"Aviation is one of the fastest-growing sources of [global warming] pollution," EDF International Counsel Annie Petsonk told the Senate committee Wednesday. "U.S. airlines say they have cut emissions by 15 percent, but … their emissions dropped with the financial crisis, and they are projected to grow."