By Dietrich Knauth NEW YORK (Reuters) -Twelve U.S. states will ask a federal court on Wednesday to halt President Donald Trump's "Liberation Day" tariffs, arguing that he overstepped his authority by declaring a national emergency to impose across-the-board taxes on imports from nations that sell more to the U.

Japan’s exports to the United States, its largest single trading partner, fell nearly 2% in April as tariff hikes imposed by President Donald Trump hit home. Globally, exports rose just 2% year-on-year,