Oil prices ticked lower on Thursday after three straight sessions of gains, as investors assessed the impact of continued U.S. military operations against Iran and the prospect of prolonged disruption to shipping through the Strait of Hormuz.

As of 06:03 ET (10:03 GMT), Brent Oil Futures expiring in September fell 0.5% to $84.52 per barrel, while Crude Oil WTI Futures} slipped 0.2% to $79.43 per barrel.

Both benchmarks surged nearly 10% to one-month highs at the start of the week when the Iran conflict reignited.

Markets remained focused on the security of the Strait of Hormuz, through which roughly one-fifth of global oil and liquefied natural gas shipments normally pass.

The latest gains followed a fresh wave of U.S. strikes launched on Wednesday against Iranian military targets linked to attacks on commercial shipping.

Washington said the operation was aimed at degrading Iran’s ability to threaten maritime traffic in the Gulf. 

Tehran said it was engaged in an "existential war" with the U.S. and warned that regional energy exports could face further disruption if hostilities continue.

The renewed conflict has reversed much of the optimism that followed last month’s temporary easing in tensions.

"The concern is that renewed oil supply disruptions come amid the large inventory drawdowns through the second quarter, leaving the market more vulnerable," ING analysts said in a note.

"In addition, global SPR releases, which have helped the market out over recent months, are set to end in the next few weeks," analysts added.

Jefferies analysts said they expect the current phase of escalation to persist for several weeks, even if it does not develop into a full-scale war, arguing that this would likely keep traffic through the Strait of Hormuz impaired and maintain upward pressure on oil prices.

Further supporting prices, the U.S. Energy Information Administration said on Wednesday crude oil inventories fell by 1.7 million barrels in the week ended July 10, largely in line with expectations.

Gasoline stockpiles declined by 1.5 million barrels as peak summer driving demand remained firm. Distillate inventories, however, unexpectedly rose by 4.6 million barrels.

The International Energy Agency said in its July Oil Market Report that while oil flows through the Strait had partially recovered in June, renewed hostilities this month have clouded the outlook and could derail expectations for a return to surplus in 2027.