The confrontation between Iran and the United States intensified sharply on Thursday, with Tehran issuing a direct warning that any renewed American military action would trigger "long and painful strikes” against U.S. positions across the region, even as the strategic Strait of Hormuz remains shut and global energy markets continue to absorb the shock.

At the center of the crisis is the world’s most critical oil transit route, where shipping has been effectively halted for two months amid the U.S.-Israeli conflict with Iran.

The closure of the Strait of Hormuz, which carries roughly one-fifth of global oil and gas flows, has turned an already volatile war into a full-scale economic pressure point, pushing Brent crude above $126 a barrel at one stage before settling closer to $114.

The sustained disruption has tightened supply chains, lifted fuel costs worldwide, and intensified warnings from economists about inflationary spillover and recession risk if the blockage continues.

Iran has framed the closure as a response to what it calls a U.S. naval blockade targeting its oil exports, which remain the backbone of its economy.

Despite a cease-fire declared on April 8, neither side has moved toward a durable settlement, and the truce has done little to ease military or maritime tensions in the Gulf.

Washington, meanwhile, is preparing for a possible escalation. U.S. President Donald Trump, the current POTUS, was scheduled to receive a briefing on expanded strike options designed to pressure Tehran back into negotiations, according to a U.S. official cited by Reuters.

The prospect of renewed military action immediately reverberated through energy markets, triggering a sharp spike in crude prices after reports first surfaced in Axios before easing later in the session.

Diplomatic progress remains minimal. Iranian Foreign Ministry spokesman Esmaeil Baghaei signaled on Thursday that expectations of a rapid breakthrough were unrealistic, underscoring the entrenched positions on both sides and the absence of a functioning negotiation track.

On the security front, reports from Iranian state and semi-official media indicated heightened air defense activity over Tehran late Thursday, including engagement of drones and surveillance aircraft.

While details remain limited, the reports added to a broader sense of regional alertness as governments responded to rising instability.

The United Arab Emirates further tightened regional precautions, banning its citizens from travel to Iran, Lebanon, and Iraq and urging those already there to leave immediately, reflecting growing concern that the conflict could widen beyond the Gulf.

Tehran’s military messaging also escalated.

A senior Islamic Revolutionary Guard Corps official warned that any fresh U.S. strike, even if limited, would trigger sustained retaliatory attacks on American positions across the Middle East.

Aerospace Force Commander Majid Mousavi added that U.S. bases and naval assets would not be exempt, reinforcing Iran’s intent to deter further escalation through direct threat.

Supreme Leader Ayatollah Mojtaba Khamenei hardened that stance further, asserting that Iran would assert full control over the waterway under what he described as a new management framework.

He rejected foreign presence in the region, signaling no intention of loosening Iran’s grip on maritime access despite international pressure.

The widening crisis has drawn stark warnings from the United Nations.

Secretary-General Antonio Guterres cautioned that prolonged disruption through mid-year could slow global growth, push inflation higher, and drive millions into poverty and food insecurity, describing the Strait as a vital artery for the world economy that becomes harder to restore the longer it remains closed.

In Washington, the political and legal clock is also ticking.

A War Powers deadline expires Friday, though U.S. officials indicate it is unlikely to change the administration’s approach given a cease-fire already in place since April.

Behind the scenes, discussions continue over possible next steps, ranging from sustained blockade measures to limited operations aimed at reopening the strait or declaring strategic success without further escalation.

At the same time, a parallel diplomatic track is taking shape. A State Department cable reportedly urges allies to consider joining a proposed maritime coalition aimed at securing navigation through the strait once conditions allow. France, Britain, and other partners have expressed conditional interest, though participation remains tied to an end to hostilities.

Iran, however, continues to link any broader regional settlement to wider political demands, including issues tied to Israel’s operations in Lebanon, where a fragile cease-fire remains in place. Iranian Foreign Minister Abbas Araqchi said those conditions remain central to any future negotiation process.