NEW YORK—U.S. stocks fell by more than 1 percent on Monday, pressured downward by surging Omicron coronavirus cases and a possible fatal blow to a $1.75 trillion U.S. domestic spending bill, with oil prices sliding more than 3 percent. U.S. stock indexes retreated more than 1 percent as positive COVID-19 case counts rose, Britain warned of tightening coronavirus curbs to limit the spread and President Joe Biden’s investment bill hit a significant setback. U.S. COVID cases have risen 50 percent this month. Investors feared that new restrictions would weigh on fuel demand, sending oil prices lower. “It was kind of a triple whammy on the economy over the weekend-Omicron, the Fed, and taking the fiscal initiative off the table,” said Jack Ablin, chief investment officer at Cresset Capital Management. “The market is taking a hit. I think it’s an economic reset that investors are kind of gauging.” The Federal Reserve …