WASHINGTON – Federal regulators on Monday upheld their earlier approval of a proposed liquefied natural gas terminal in Fall River, Mass., handing a setback to opponents of the project.

Fall River officials and other project foes had asked the Federal Energy Regulatory Commission to reconsider its previous approval of the project in light of new plans by the company building the LNG terminal, Weaver’s Cove Energy, to use a fleet of smaller tankers.

FERC’s ruling noted that the Coast Guard “exercises regulatory authority over LNG facilities that affect the safety and security of port areas and navigable waterways.”

The Coast Guard is currently reviewing the plan by Weaver’s Cove to use smaller tankers.

Officials from Massachusetts and Rhode Island oppose the project, citing safety concerns and disruptions from the intense security required for LNG tanker deliveries through Narragansett Bay.

The smaller tankers were needed to pass through a narrow bridge that project foes are hoping will block development of the proposed facility.

Project opponents, including Rep. James McGovern, D-Worcester, inserted a provision in the federal highway bill last summer that banned demolition of the old Brightman Street Bridge which sits before the terminal, preventing supertankers from passing through.

Fall River Mayor Edward Lambert, who opposes the project, said he was not surprised by FERC’s decision.

“We felt all along that FERC is a proponent of the project and we disagree with their decision,” Lambert said. “We’re not relying on FERC to be the ultimate challenge to this project. We still have a number of challenges.”

Weaver’s Cove officials did not have an immediate comment on the FERC decision.

Lambert said project foes are also pursuing a legal challenge. Opponents filed an appeal with the 1st U.S. Circuit Court of Appeals in Boston earlier this year, alleging that safety and legal issues were not considered by federal officials who approved the project.