A judge's recent ruling that environmental studies were inadequate for a subway line that would tunnel under Beverly Hills will not slow construction of the project, Metro officials said Monday.

The Purple Line subway would connect downtown Los Angeles to Westwood along a route that mostly tracks under Wilshire Boulevard. An already completed segment of the line currently runs as far as Wilshire and Western. Construction on the next section has already begun for stations along Wilshire at La Brea, Fairfax and La Cienega avenues.

In 2012, Beverly Hills and the Beverly Hills Unified School District sued the Federal Transit Administration over a planned segment tunneling under Beverly Hills high School. The FTA arranges funds for and must sign off on Metro's plans for the Purple Line Extension.

The city and school district claimed Metro's environmental and seismic studies didn't take into account various earthquake faults, former oil fields and pockets of underground methane gas the tunnel would traverse. An active oil derrick sits adjacent to Beverly Hills High School in a wooden structure that's been painted over with flowers.

In a ruling Friday, U.S. District Judge George H. Wu agreed the studies were inadequate and ordered Metro to redo them.

Metro spokesman Dave Sotero said the judge's ruling means that Metro will revise its studies but not scrap the planned route under the high school.

"Nothing that has been done in a legal case has affected the timeline for the Purple Line Extension," he said.

Metro expects to sign an agreement to receive $1.5 billion in federal grants and loans by the end of the year, with construction on the Beverly Hills/Century City segment beginning by 2018. That segment includes a station at Wilshire and Rodeo Drive and at Constellation Way in Century City.

It's unclear whether Beverly Hills and the school district will continue to oppose the proposed route.

"Beverly Hills would like to see a rigorous environmental review of the proposed routing of the Purple Line under Beverly Hills High School, including an analysis of the risks from nearby earthquake faults, the air quality impacts of construction just feet from the high school and of tunneling through a former oil field with known pockets of methane gas," said city spokeswoman Therese Kosterman.

A spokesperson for the school district did not return requests for comment Monday.

The final miles of the Purple Line Extension would take until about 2035 to complete.