By Andrew Chung

Feb 6 (Reuters) - The U.S. Supreme Court declined on Thursday to place on hold a dispute over California's standards for vehicle emissions and electric cars even as President Donald Trump's administration considers policy shifts that touch upon pending litigation at the nation's highest judicial body.

The justices denied the administration's request to pause further action in the case, as well as two cases concerning which courts may hear challenges to EPA rules. The justices previously agreed to take up these cases but have not yet heard arguments in them.

The justices, however, granted a request to put on hold a dispute over a rule issued by Democratic former President Joe Biden's administration that would make it easier for students defrauded by their colleges to have their loans forgiven.

As is customary, the court did not explain the reasons for these decisions, issuing only brief orders in each case.

Trump, a Republican, began his second term as president on January 20. Legal experts expect his administration to change positions from the ones taken under Biden in a number of major cases at the court.

These include one involving Tennessee's ban on gender-affirming medical care for transgender minors and another one concerning a federal regulation targeting largely untraceable firearms called "ghost guns," though those were not among the cases placed on hold.

The justices on December 13 agreed to hear the dispute over California's vehicle standards, which involves a 2022 exception given to that state by the U.S. Environmental Protection Agency during Biden's presidency to national vehicle emission standards set by the agency under the Clean Air Act anti-pollution law.

A Valero Energy VLO.N subsidiary and fuel industry groups appealed a lower court's rejection of their challenge to the EPA's waiver decision.

States and municipalities are generally preempted from enacting their own standards. But Congress let the EPA waive the preemption rule to allow Democratic-governed California to set certain regulations that are stricter than federal standards.

The EPA's action reinstated a waiver for California to set its own tailpipe emissions limits and zero-emission vehicle mandate through 2025, reversing a 2019 decision during Trump's first term in office rescinding the waiver.

In asking the Supreme Court to pause the case, Acting Solicitor General Sarah Harris had said in a January 24 filing, "After the change in administration, EPA's acting administrator has determined that the agency should reassess the basis for and soundness of the 2022 reinstatement decision."

(Reporting by Andrew Chung in New York; Editing by Will Dunham)

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