WASHINGTON - US Supreme Court justices raised doubts on Wednesday over the legality of President Donald Trump's sweeping tariffs in a case with implications for the global economy that marks a major test of Trump's powers.

Both conservative and liberal justices sharply questioned the lawyer representing Trump's administration about whether the president had intruded on the power of Congress in imposing tariffs under a 1977 law meant for use during national emergencies.

But some of the conservative justices also signaled that they were wrestling with their recognition of the inherent power that presidents have in dealing with foreign countries, suggesting the court could be sharply divided in the outcome of the case. The court has a 6-3 conservative majority.

During arguments lasting more than 2-1/2 hours, the justices asked US Solicitor General D. John Sauer whether Trump's application of this statute to impose tariffs of unlimited duration was a major action by the executive branch that would require clear congressional authorization.

Those questions related to the Supreme Court's "major questions" doctrine, which requires executive branch actions of vast economic and political significance to be clearly authorized by US lawmakers.

The arguments came in appeals pursued by the administration after lower courts ruled that his unprecedented use of the law at issue to impose the tariffs exceeded his authority. Businesses affected by the tariffs and 12 US states, most of them Democratic-led, challenged the tariffs.

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