The US is working to finalize an announcement that would end the stacking of universal tariffs on Japanese goods, a senior Trump administration official said Friday.

Japan has been seeking clarification, as a lack of written confirmation of the deal it struck with the U.S. last month has led to confusion over whether President Donald Trump's tariffs that took effect on Thursday will be stacked on top of existing levies.

The U.S. government on Thursday promised to amend a presidential executive order to remove overlapping tariffs on Japanese goods, Tokyo's trade negotiator said, after talks in Washington to fix what he called a "regrettable" oversight.