Oil markets fluctuated in Asian trading on Monday following a stark warning from US President Donald Trump, who threatened to target key infrastructure in Iran if shipping access through the Strait of Hormuz is not restored.

In a profanity-filled post on social media Sunday, Trump warned that the United States could strike Iranian power plants and bridges unless the strategic waterway is reopened by late Tuesday, US time.

Benchmark Brent crude briefly climbed above $110 (£83.38) per barrel before retreating, as reports emerged suggesting possible talks between Washington and Tehran on a ceasefire.

Energy flows from the Middle East remain heavily disrupted, with Iran warning it may attack vessels attempting to pass through the strait. The threats come in response to US and Israeli airstrikes that began on 28 February.

Axios reported that US, Iranian and regional intermediaries are engaged in discussions over a proposed 45-day ceasefire that could pave the way toward a longer-term resolution, citing sources from the US, Israel and the region.

The report has not been independently confirmed by BBC News, and the White House did not immediately comment.

By late morning in Asia, Brent crude was up 0.7% at $109.80 per barrel, while US oil prices showed little movement, holding at $111.62.

Sushant Gupta of consultancy Wood Mackenzie said markets are likely to remain sensitive to developments in the conflict. He noted that price swings will track both escalation and signs of de-escalation.

He added that the key issue remains whether Gulf energy exports can resume, helping to alleviate a global supply crunch.

The Strait of Hormuz, a narrow but critical passage, typically carries about one-fifth of global energy shipments. Ongoing disruptions have driven up energy costs worldwide and heightened fears of rising inflation.

Oil prices surged past $100 per barrel last week after Trump intensified rhetoric toward Iran, warning that continued US strikes could send the country “back to the Stone Ages.”

Over the weekend, Iranian forces continued targeting oil-related infrastructure across the الخليج region.

Tehran claimed responsibility Sunday for coordinated attacks on petrochemical facilities in Kuwait, Bahrain and the United Arab Emirates.

On Monday, Iran’s Islamic Revolutionary Guard Corps warned it would escalate strikes on US economic interests if attacks on civilian infrastructure inside Iran persist.

Meanwhile, Opec+—which includes major producers such as Saudi Arabia and Russia—agreed Sunday to a modest production increase for May.

However, the planned rise of 206,000 barrels per day is expected to have limited impact, as several member states are constrained by the ongoing conflict.

Trump has previously delayed deadlines for Iran to halt its threats against maritime traffic but reiterated his stance in the latest social media posts.

Trump wrote on Sunday: "Tuesday will be Power Plant Day, and Bridge Day, all wrapped up in one, in Iran. There will be nothing like it!!! Open the Fuckin' Strait, you crazy bastards, or you'll be living in Hell - JUST WATCH! Praise be to Allah. President DONALD J. TRUMP".

A few hours later, in a post on the same platform he said: "Tuesday, 8:00 P.M. Eastern Time!"

In an interview with Fox News, Trump said there was a “good chance” of reaching an agreement on Monday, but warned he was also weighing the option of “blowing everything up and taking over the oil” if negotiations fail.

Senior Iranian military official Gen Ali Abdollahi Aliabadi rejected an earlier US deadline, describing it as “helpless, nervous, unbalanced and stupid,” and warning that “the gates of hell will open” for the US leader.