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U.S. stock futures rose Tuesday as investors balanced optimism over a potential deal to end the U.S.-Iran war against fresh American military strikes in the country, according to CNBC.

Futures on the Dow Jones Industrial Average were up 234 points, equivalent to a 0.5% gain, while S&P 500 futures added 0.7% and Nasdaq $NDAQ +0.66%-100 futures rose 1.1%. Monday's session was not held, as U.S. markets observed the Memorial Day holiday.

Tuesday morning saw Brent crude push back above $96 a barrel, a gain of roughly 3% that clawed back some of the ground lost when prices slid under $94 the previous session, according to The Wall Street Journal. West Texas Intermediate futures traded about 4% lower on the day, according to CNBC. For investors, the $100 level carries symbolic weight — prior to Monday, Brent had not closed beneath that price in over a month, according to The Wall Street Journal.

On Monday, Trump offered an upbeat assessment of diplomatic efforts, telling reporters that Iran talks were going well, while also putting Tehran on notice that Washington was prepared to shift to an offensive posture if the process falls apart, according to CNBC. At the same time, fresh military action unfolded: Tim Hawkins, the spokesman for U.S. Central Command, confirmed that American forces hit targets in southern Iran, among them missile launch infrastructure and watercraft believed to be engaged in mine-laying operations, framing the strikes as defensive moves taken within the bounds of an active ceasefire, according to CNBC.