WASHINGTON (Reuters) - U.S. Environmental Protection Agency chief Andrew Wheeler said on Tuesday the Trump administration has more actions “in the works” related to excess vehicle emissions after imposing major penalties on automakers.

FILE PHOTO: Acting Administrator of the Environmental Protection Agency Andrew Wheeler speaks during an event hosted by U.S. President Donald Trump with workers on "Cutting the Red Tape, Unleashing Economic Freedom" in the Oval Office of the White House in Washington, U.S., October 17, 2018. REUTERS/Joshua Roberts

In January, Fiat Chrysler Automobiles NV agreed to an $800 million settlement to resolve claims by the U.S. Justice Department and the state of California that it used illegal software to produce false results on diesel-emissions tests after a bringing a record-setting case against Volkswagen AG.

Wheeler said EPA career staff in the Fiat Chrysler case worked diligently after the company assured the agency that it did not use defeat devices.

“We will continue to do work like that and we have had other enforcement actions against other auto companies ... We are moving forward, we have other cases in the works,” Wheeler told a U.S. House Appropriations Committee panel Tuesday.

“When people are not playing by the rules and they are creating more pollution ... we will catch them, we will hold them accountable,” he added.

The Justice Department said in January the Fiat Chrysler settlement does not resolve an ongoing criminal investigation into the Italian-American automaker’s conduct.

A federal judge in San Francisco has set a May 3 hearing to grant final approval to the civil settlement.

Volkswagen admitted in September 2015 that it intentionally evaded emissions rules and agreed to pay more than $25 billion in the United States to owners, regulators, states and dealers, including spending as much as $15 billion to buy back about 500,000 polluting U.S. vehicles.

German auto supplier Robert Bosch GmbH, which provided the emissions control software for the VW and Fiat Chrysler vehicles, also agreed to pay $27.5 million to resolve claims from Fiat Chrysler diesel owners in January.

U.S. regulators are also investigating Daimler AG for alleged excess emissions in Mercedes-Benz diesel vehicles, but the Justice Department and EPA have declined to comment on the status of the probe.

Daimler declined to comment, but has previously acknowledged it faces investigations in Germany and the United States.

In February, Ford Motor Co said it hired outside experts to investigate its vehicle fuel economy and testing procedures after employees raised concerns. The automaker added that it did not know whether it would have to correct data provided to regulators or consumers.

Ford says the issues do not involve the use of so-called defeat devices - hardware and software designed deliberately to deceive government emissions tests. Ford has been in talks with the EPA and shared significant data since February, including communications from employees.