Both houses of the U.S. Congress have passed a bill that would limit air pollution from domestic and international shipping, essentially holding the United States to the same conditions as the MARPOL Annex VI, officials said Wednesday.

To become law, the bill must be signed by President George Bush. Officials from the American Association of Port Authorities (AAPA) said both the Environmental Protection Agency and Department of Homeland Security had endorsed the bill and expect the president will sign it.

“All our members were very supportive of getting this legislation passed,” said Meredith Martino, AAPA’s manager of government relations and environmental policy. “I think we can expect the president will sign the bill.”

If the bill becomes law, international limits on NOx and SOx in U.S. waters will be enforced by the U.S. Coast Guard.

The bill was first introduced in the House of Representatives by James Oberstar, a Democrat from Minnesota, and passed with broad support from both Democrats and Republicans in April. The Senate voted unanimously in favor of the bill two weeks ago; and it left Congress for the president’s desk Tuesday.