A Superior Court judge has rejected a motion by the city of Los Angeles to dismiss the lawsuit filed by Ontario to wrest control of the airport in its own backyard from L.A.

Attorneys for Los Angeles challenged the lawsuit during a court hearing this week, arguing Ontario had no legal grounds to sue because, as part of a joint-powers agreement, Ontario had decades ago agreed to sell L.A./Ontario International Airport to Los Angeles.

Los Angeles World Airports — which operates Los Angeles International Airport, Van Nuys Airport and L.A./Ontario International — is a department of the city of Los Angeles.

The case is being handled in Riverside County because neither Ontario nor Los Angeles is in that jurisdiction.

The city of Ontario can now proceed with its lawsuit, which aims to rescind or reform terms of the agreement. City officials want to hold the airport administration accountable for the decline in passengers at ONT and dissolve the 1967 agreement that gave control of the airport to Los Angeles.

The 25-page suit contends LAWA is in breach of contract for failing to bring in and retain service at ONT, failing to properly market the airport, and abandoning plans to redistribute air traffic throughout the region.

“There’s not a scintilla of evidence that Los Angeles has no desire to operate this airport,” said Steve Rosenthal, who represents the city of Los Angeles. “We have every desire, otherwise we wouldn’t be here if we didn’t have the desire to continue operation of Ontario as a vibrant, growing airport in this area.”

Ontario officials estimate ONT will have 3.9 million passengers this year, a 46 percent drop from when traffic peaked at 7.2 million in 2007. The airport served 4.3 million passengers in 2012.

Another alternative for Ontario could be to seek injunctive relief and a judicial order to return the airport to Ontario.

“This is the only remedy that would provide complete relief to the city of Ontario” Cronthall said. “(Otherwise) Ontario Airport may go into ruin.”

The next hearing is Dec. 2 for a status conference on the case.