A federal appeals court has ruled that the Navy must protect endangered whales from the potentially lethal effects of underwater sonar during anti-submarine training off the Southern California coast, rejecting President Bush's attempt to exempt the exercises from environmental laws.

In a Friday night ruling rushed into print ahead of the next scheduled exercise on Monday, the Ninth U.S. Circuit Court of Appeals in San Francisco upheld a federal judge's decision that no emergency existed that would justify Bush's intervention.

The Navy is engaged in "long-planned, routine training exercises" and has had ample time to take the steps that the law requires - conduct a thorough review of the environmental consequences and propose effective measures to minimize the harm to whales and other marine mammals, the three-judge panel said.

The court noted that the Navy has been conducting similar exercises for years, has agreed in the past to restrictions like the ones it is now challenging, and was sued by environmental groups in the current case nearly a year ago. The lower-court judge reviewed the evidence and found nothing to support the Navy's claim that the protective measures would interfere with vital training or hamper national security, the court said.

Past rulings have established that "there is no 'national defense exception' " to the National Environmental Policy Act, the court said. That law requires government agencies to review projects that might harm the environment and propose reasonable protective measures.

The ruling sets a precedent for federal courts in California and eight other Western states. One of those states is Hawaii, where a federal judge on Friday ordered similar restrictions on Navy sonar exercises off the Hawaiian islands. The ruling by U.S. District Judge David Ezra includes requirements to reduce sonar when whales are detected within certain distances or when conditions make monitoring difficult.

The Navy has completed six of the 14 large-scale training exercises scheduled off Southern California between February 2007 and January 2009. It decided not to conduct a full environmental review before the operations, saying it had already agreed to post lookouts for whales and taken other adequate protective measures.

In an August 2007 ruling, U.S. District Judge Florence-Marie Cooper of Los Angeles said the Navy's measures were "woefully ineffectual and inadequate" and would leave nearly 30 species of marine mammals at risk, including five species of endangered whales.

She said the Navy's own research shows that its use of mid-frequency sonar can damage the hearing of whales and dolphins, can interfere with their ability to find food and mate, and has been linked to the beaching of whales.