Federal auto safety regulators played a significant role in General Motors Co's (GM.N) failure to promptly report and recall cars with defective parts that led to at least 19 deaths, a congressional report said on Tuesday.

The report, made public ahead of a separate hearing on Tuesday, said officials at the National Highway Traffic Safety Administration repeatedly failed to identify the potential problems with the faulty ignition switches and could have acted more quickly to catch the problem.

"It is tragic that the evidence was staring NHTSA in the face and the agency didn't identify the warnings," said Representative Fred Upton, chairman of the House Energy and Commerce committee, which released the findings.

Representatives for the agency could not be immediately reached for comment.

The Senate Commerce, Science and Transportation Committee is set to examine oversight and policy issues of the safety agency at a hearing scheduled for 2:30 p.m.

NHTSA Deputy Administrator David Friedman, who is due to testify at the panel, has rapped GM for its "flawed" culture on recalls, saying the automaker put its own reputation ahead of the safety of its customers.

Other government and industry transportation safety officials also are scheduled to testify.

According to the House panel's findings, first reported by the Detroit Free Press and the New York Times, NHTSA staff had the power and information that they needed to act over the faulty GM switches.

But they were hampered by "lack of knowledge and awareness regarding the evolution of vehicle safety systems they regulate," the report said.

Representative Tim Murphy, head of the House panel's investigative subcommittee, said congressional investigators found that some of the same problems at GM "also plagued its regulator," including "a lack of accountability, poor information sharing and a fundamental misunderstanding of the vehicles."

"Both GM and NHTSA had a responsibility to act and both share culpability in this safety failure," he said.