What level of tariffs will the U.S. impose on imports and when? Stock futures were falling early Monday as markets were roiled by threats of new levies but also confusion over the deadline for the proposed duties.

Stock index futures traded sharply lower on Monday, as President Donald Trump threatened an extra 10% tariff for countries aligning with the 'Anti-American policies of BRICS.' S&P 500 futures ( SPX) -0.5%, Nasdaq 100 futures ( US100:IND) -0.6%, and Dow futures ( INDU) -0.3%.