Oil prices rose for a second day on concerns of supply tightening due to new U.S. sanctions on Iran and strong global refining margins. Brent crude futures rose 0.5% to $75.16 a barrel, while U.S. West Texas Intermediate crude futures gained 0.7% to $71.17 a barrel. The U.S. imposed new sanctions on brokers, tanker operators, and shipping companies involved in transporting Iranian oil. Uncertain demand outlooks, including potential tariffs on Canadian and Mexican imports, capped the gains. The market also viewed President Trump's warming relations with Russia as a potential signal of easing sanctions, which could add to global oil supply.