U.S. stock index futures made slight gains late Sunday amid rising tensions between the U.S. and China. As of 11:30 p.m. Eastern, Dow Jones Industrial Average futures /zigman2/quotes/210407078/delayed YM00 +0.51% , were up 70 points, or 0.3%, while S&P 500 futures /zigman2/quotes/209948968/delayed ES00 +0.41% and Nasdaq-100 futures /zigman2/quotes/210219788/delayed NQ00 +0.35% tracked similarly. U.S. equity markets are closed Monday for the Memorial Day holiday. Stocks were little changed on Friday but for the week, the Dow /zigman2/quotes/210598065/realtime DJIA +1.44% climbed 3.3%, the S&P 500 /zigman2/quotes/210599714/realtime SPX +1.05% advanced 3.2% and the Nasdaq Composite /zigman2/quotes/210598365/realtime COMP +0.66% rose 3.4%. Traders are keeping an eye on how the U.S. and other global economies are faring as businesses gradually reopen from coronavirus-related shutdowns. But new tensions between the U.S. and China have risen, with a top White House aide saying Sunday that the U.S. may sanction China if a bill limiting Hong Kong's autonomy is approved.