General Motors Co. will pay a record $35 million fine for waiting years to notify federal investigators about an airbag flaw that has led to at least 13 deaths. The company will be subject to what the National Highway Traffic Safety Administration described Friday as “unprecedented” supervision by the government.

Although the fine—the maximum allowed by law—is the biggest civil penalty ever for failing to report a safety defect promptly, Secretary of Transportation Anthony Foxx on Friday called it “a rounding error.” He’s asked Congress to raise the top penalty to $300 million, an amount he called “attention grabbing and capable of creating a deterrent value for automakers.”