U.S. Customs and Border Protection told a federal judge it cannot immediately comply with an order to refund Trump's illegal tariffs totaling $166 billion. The agency filed the response Friday as Judge Richard Eaton prepared to hold a hearing on refund requests from importers.

Eaton had ordered CBP to begin calculating refunds for importers who paid IEEPA tariffs deemed illegal by the Supreme Court. The judge noted that CBP routinely processes refunds and liquidates entries daily, suggesting the agency has the technical capability to execute the order.

CBP's filing stated that over 330,000 importers have made more than 53 million entries involving these tariffs since last year. The agency's executive director of trade programs said the sheer volume of transactions makes immediate compliance impossible. This legal standoff highlights the massive scale of Trump's tariff program and the logistical challenges of unwinding it after the Supreme Court's ruling.