SAN FRANCISCO — A federal appeals court on Wednesday refused to weigh in on a thorny issue that could complicate California’s plans for a $64 billion bullet train between Los Angeles and San Francisco.

Three judges with the 9th U.S. Circuit Court of Appeals said they lacked authority to rule on a federal agency’s determination that it has the power to pre-empt California’s strict environmental law.

The finding by the U.S. Surface Transportation Board in 2014 created uncertainty for lawsuits filed against the state’s high-speed rail project under the California Environmental Quality Act.

The California Supreme Court last week contradicted the surface transportation board, ruling in a separate case that federal law does not allow state-owned rail projects to completely bypass CEQA.

The 9th Circuit said it lacked jurisdiction because the transportation board’s finding was advisory and had no legal consequences.

A 9th Circuit ruling that reached the opposite conclusion and sided with the surface transportation board would have made the issue ripe for U.S. Supreme Court review, said Richard Frank, an environmental law expert at the University of California, Davis School of Law.

The California Supreme Court ruling now appears more likely to stand, Frank said. That decision ensures further legal complications for the high-speed rail project.

The state’s High-Speed Rail Authority said in a statement it will continue to adhere to both federal and state environmental requirements.