Oil prices fell 9% after Iran announced the Strait of Hormuz was open for commercial vessels, lifting Brent to $90.38 and WTI to $83.85. Brent futures settled down $9.01, or 9.07%, to $90.38 after a session low of $86.09. WTI futures fell $10.48, or 11.45%, to $83.85 after touching $80.56. Both contracts made their largest daily declines since April 8. Following weeks of heightened risk premiums amid U.S.–Iran negotiations, the market is rapidly unwinding the extreme risk premium built over the past two weeks, crude is shifting back toward pricing actual flow normalization rather than disruption risk, Gelber & Associates analysts said. "All ships can sail through the Strait of Hormuz but this needs to be coordinated with Iran's Islamic Revolutionary Guard Corps," a senior Iranian official told Reuters, adding that unfreezing Iranian funds was part of the deal. Around 20 ships were seen moving from the Gulf towards the exit via the Strait of Hormuz, according to ship tracking data. President Trump said the U.S. would enter Iran at a "leisurely pace" to recover enriched uranium, adding that Tehran had offered to not possess nuclear weapons for more than 20 years. "We're going to see what happens. But I think we're very close to making a deal with Iran," Trump told reporters outside the White House on Thursday. A U.S. official confirmed a military blockade involving more than 10,000 personnel remains in effect. While the opening of the strait was a step in the right direction, the European market would remain tight for a while, SEB Research analyst Ole Hvalbye said, since it takes roughly 21 days for ships to move from the Gulf to Rotterdam, the main crude port in the region. Traffic could be halted once again in the strait, if an agreement about Iran's nuclear ambitions and lifting of the U.S. sanctions remains elusive, said Tamas Varga , an analyst at PVM Oil Associates . In the U.S., energy services firm Baker Hughes reported that the number of oil and natural gas rigs operating fell for a second straight week, the first time since March.