NEW YORK -- US President Donald Trump said Saturday he will raise the new global tariff to 15 percent, one day after he announced a 10 percent worldwide duty following a heavy blow from the Supreme Court.

"I, as President of the United States of America, will be, effective immediately, raising the 10% Worldwide Tariff on Countries, many of which have been 'ripping' the US off for decades, without retribution (until I came along!), to the fully allowed, and legally tested, 15% level," Trump wrote in a social media post on Saturday.

He added that during the next short number of months, his administration will "determine and issue the new and legally permissible Tariffs, which will continue our extraordinarily successful process of Making America Great Again - GREATER THAN EVER BEFORE!!!"

US Supreme Court ruled Friday morning in a 6-3 vote that Trump's tariff policy under the International Emergency Economic Powers Act was illegal.

Infuriated by the ruling, Trump signed an order imposing a 10 percent tariff on imports from all countries hours later.