WASHINGTON — Toyota is expected to agree to a fine of more than $16 million for failing to promptly report to the government problems with sticking gas pedals on its vehicles, a Transportation Department official said.

Toyota faces a deadline today to accept or contest the $16.4 million fine, the largest ever assessed by the government against an automaker, over evidence it knew about the defective gas pedals in September but did not issue a recall until January.

Under federal law, automakers are required to notify the government within five business days when they find a potential safety defect.

The Transportation official said Toyota is expected to pay the full amount of the fine within 30 days as a way of avoiding going to court against the government. The official was not authorized to speak publicly and spoke only on condition of anonymity.

The official said Toyota did not intend to admit wrongdoing explicitly but the company still faces dozens of personal injury and wrongful death lawsuits in federal courts. Federal prosecutors and the Securities and Exchange Commission are conducting investigations related to the recalls.

From the government's viewpoint, the official said, the agreement to pay the full fine constituted an acceptance of responsibility for hiding the safety defect in violation of the law.

Toyota declined to comment on the fine.