Crude futures were little changed in midday trading as prospects for a US-Iranian peace deal faded after President Trump said no talks were taking place with Iran, with the two sides remaining far apart on a host of issues, including control of the Strait of Hormuz.
Front-month West Texas Intermediate crude futures were up by 0.8% to $85.04 per barrel, while Brent futures eased 0.5% to $91.31/bbl.
Gelber & Associates said that Iran has signaled a more aggressive posture, while Trump declined to set another deadline and threatened Oman if it interferes with US efforts.
On Tuesday, Trump said no talks were taking place with Iran, and none were scheduled, while insisting that the strait was open, contradicting an earlier Iranian assertion that the strategic waterway remained shut to shipping.
Monday marked the day by which Tehran and Washington were expected to reach a final deal under a memorandum of understanding agreed in June.
The US president said that the US blockade of Iranian ports remains in full force and effect, while claiming that "all water mines have been removed or detonated."
Meanwhile, Mohammad Bagher Ghalibaf, Iranian speaker of parliament and top negotiator, reportedly said that the strait would remain shut until the US met the conditions of an interim deal signed with Iran in June.
Ghalibaf said that the conditions include the US lifting its blockade of Iranian ports, lifting oil sanctions, releasing Tehran's frozen assets, and ending threats and military operations on all fronts.
However, despite Trump's claims that the strait is "open and operating", the UK Maritime Trade Operations said on Tuesday that a vessel was struck by an unknown projectile while transiting outbound in the Hormuz, causing engine room damage and a crew casualty.
The remaining crew was being assisted by the Omani Coast Guard, according to the report.
Yemen's Houthis also attacked vessels they described as a Saudi military ship and four escorts in the Red Sea, the group's spokesperson, Yahya Saree, said on Telegram on Monday.
Gelber & Associates said that an attack on a cargo ship early Tuesday and continued low transit activity through the strait reinforced those supply concerns, while disruptions in Russia and the Middle East are also tightening the global diesel market.
Commercial vessel traffic via the strait last week while vessel movements through the Bab el-Mandeb strait increased, according to the latest data from Kpler.
Confirmed crossings through Hormuz dropped 19.5% to 95 vessels last week from 118 previously, MarineTraffic data showed on Monday, while traffic through Bab el-Mandeb, the southern gateway to the Red Sea, increased 6.7% last week to 254 crossings from 238 in the week prior.