The reopening of the Strait of Hormuz remains uncertain as Iran and the United States continue to hold firm to their positions, with neither side showing signs of backing down.

The United States on Thursday said that it could maintain a naval blockade of Iran indefinitely and would ratchet up economic pressure on Tehran as ceasefire talks have stalled.

Defense Secretary Pete Hegseth told reporters that the US military has the capability to maintain a naval presence in the region to enforce its blockade of Iran.

"Indefinitely the United States Navy can maintain a blockade like that because we'll rotate ships in and out, as we have, and we'll continue to," Hegseth said.

Treasury Secretary Scott Bessent said on Thursday that the US planned to impose additional financial measures on Iran.

"Watch this space for more announcements coming next week because we are going to apply measures like have never been seen in the history of economic isolation on a country," he said in an interview on Newsmax's "Rob Schmitt Tonight" program.

Tehran has said it will not allow the waterway to reopen until its conditions are met. Conditions include removing economic sanctions and releasing frozen Iranian assets.

On Thursday, Iran's main military command, the Khatam al-Anbiya Central Headquarters, said that no commercial vessel or oil tanker has been or will be able to cross the Strait of Hormuz safely without the Iranian armed forces' permission and supervision.

In a video message released by Iranian media, Ebrahim Zolfaghari, the headquarters' spokesman, said that, as in the past, the Strait of Hormuz is under Iran's full control and management, rejecting US claims of normal vessel passage through the Strait as "false and nothing but lies."

Zolfaghari stressed that Iran's armed forces are monitoring all movements by the United States and Israel in the region, and will defend Iranian people's rights, the nation's sovereignty and aspirations, and will respond to any threat.

Mohammad Mokhber, a senior adviser to Iran's Supreme Leader Mojtaba Khamenei, said Thursday that the war would enter an offensive phase if Tehran's conditions were not met.

"The Supreme Leader's definitive strategy is for the war to become offensive if Iran's conditions are not fulfilled," Mokhber said in a post on X.

The standoff has already had a significant impact on shipping through the strategic waterway. Shipping traffic through the Strait of Hormuz dropped to eight vessels on Tuesday, compared with a 10-day average of roughly 12 vessels and 130 to 140 ships before the war.

The disruption is adding additional pressure on the global economy. The International Energy Agency on Wednesday forecast a decline in global oil supply of 4.3 million barrels per day, or around 4%, this year. A month earlier, the agency had forecast a drop of 3.7 million barrels per day.

Market concerns were further heightened by reports that Yemen's Iran-aligned Houthis targeted a Saudi Aramco refinery with drones, rekindling concerns over potential regional escalation.

Economists have forecast a sharp drop in global growth as a result of the war, and potentially a swing into recession in some areas, warning that the impact will grow if the war is not ended soon.

(With input from agencies)