Southern California’s largest water supplier was temporarily blocked from buying sprawling farmland that could be used to help build twin tunnels under the Sacramento-San Joaquin River Delta, a court ruled Tuesday.

The state’s 3rd District Court of Appeal in Sacramento granted a temporary restraining order the day before escrow was set to close on Metropolitan Water District’s $175 million deal for 20,000 acres. The ruling delays the district’s purchase by no more than a few weeks, Metropolitan attorney Catherine Stites said.