US equity indices were mostly lower on Monday as rising oil prices revived concerns about an incoming Federal Reserve rate hike. S&P 500 and Nasdaq 100 futures fell as much as 0.5%, while Dow futures were marginally below flat. Oil and refined-product wholesale prices gained after the US and Iran exchanged fresh strikes, following signals from both sides that tankers and vessels could face blockades in the Persian Gulf. The developments prolonged the suspension of exports from the region, pushed yields higher across the curve and pressured credit-sensitive equities. Microsoft, Palantir, Alphabet and Tesla each fell as much as 1% premarket, while JPMorgan and Visa declined 0.7%.