President Donald Trump announced Saturday morning that he will raise the existing 10% worldwide tariff to 15%, escalating his administration's trade agenda a day after a Supreme Court ruling addressing his tariff authority.

In a post on Truth Social, Trump blasted what he called a "ridiculous, poorly written, and extraordinarily anti-American decision on Tariffs issued yesterday" by the high court, saying that after a "thorough, detailed, and complete review," he would act immediately.

"Please let this statement serve to represent that I, as President of the United States of America, will be, effective immediately, raising the 10% Worldwide Tariff on Countries… to the fully allowed, and legally tested, 15% level," Trump wrote.

He added that during the "next short number of months," his administration will "determine and issue the new and legally permissible Tariffs," describing the move as part of what he called an "extraordinarily successful process of Making America Great Again — GREATER THAN EVER BEFORE!!!"

The Supreme Court's ruling this week addressed the scope of presidential authority in imposing tariffs, with the justices weighing limits under existing trade and emergency powers statutes.

While the administration has characterized the decision as flawed, Trump signaled that it still leaves room for higher duties within what he called "fully allowed" and "legally tested" levels.

Tariffs have been a central pillar of Trump's economic strategy, which he argues protects American workers, reduces trade deficits, and pressures foreign nations he says have "been 'ripping' the U.S. off for decades."

Critics, however, warn that broad-based tariffs risk higher consumer prices and retaliatory measures from trading partners.

Saturday's announcement underscores that, despite legal scrutiny, the administration views expanded tariffs as a key component of its economic and trade policy moving forward.