The Obama administration said on Wednesday that it would take the first step toward regulating greenhouse gas emissions from airplanes, but it acknowledged it would most likely take years before stringent standards are enacted.

The Environmental Protection Agency said that emissions from airplanes endanger human health because of their contribution to global warming. This finding does not impose specific new requirements on airlines yet, but it requires the agency to develop the rules, as it has done for motor vehicles and power plants.

Given the extended timetable of the rule-making process, and the lobbying by the airlines that international regulations should apply to all the carriers, it is almost impossible that airplane emissions rules will be completed during the Obama administration. The legal obligation for completing work on the airplane pollution rules would then fall to the next president.

The announcement represents the latest of Mr. Obama’s major initiatives to combat global warming. Next week, the agency is expected to propose new rules on emissions from heavy-duty trucks, and in August it is expected to announce new rules to rein in power plant pollution.