Global oil prices surged and stock markets across Asia tumbled on Monday as the US-Israel conflict with Iran moved into its fifth week.

Brent crude climbed more than 3%, rising above $115 (£86.77) per barrel, while US benchmark oil advanced nearly 2% to $101.62. The latest jump puts Brent on course for its largest monthly increase on record.

Japan's Nikkei 225 dropped 2.8%, and South Korea’s Kospi ended the day down by almost 3%.

The market turbulence followed weekend developments in which Iran-backed Houthi fighters in Yemen entered the conflict by launching strikes against Israel. Meanwhile, Iran warned it could broaden its retaliatory attacks to include universities and the residences of US and Israeli officials.

US President Donald Trump said in a newspaper interview on Sunday that the United States could "take the oil in Iran" and potentially seize Kharg Island, a key Iranian oil export terminal.

Responding to a question about Iran’s defenses on the island, he said: "I don't think they have any defence. We could take it very easily."

Trump likened the possible action to the situation in Venezuela, where the US intends to maintain control over the oil sector "indefinitely" following the January removal of then-President Nicolás Maduro.

Over the weekend, Iran’s parliamentary speaker stated that Iranian forces were "waiting for American soldiers" as an additional 3,500 US troops were deployed to the region.

Energy markets worldwide have experienced sharp swings since Tehran responded to US and Israeli attacks by threatening to target vessels attempting to pass through the Strait of Hormuz.

Lars Jensen, a shipping analyst and former Maersk executive, cautioned that even if the Strait of Hormuz were to reopen immediately, price pressures would likely persist.

"We need to remember that much of the oil loaded in the Persian Gulf before this crisis is only just reaching refineries now," he explained.

Jensen added that the broader consequences of the US-Israel conflict with Iran could be "considerably greater" than the oil crisis of the 1970s, which triggered widespread economic disruption.

Now head of Vespucci Maritime consultancy, Jensen also highlighted potential knock-on effects for global food costs.

He said: "Between 20% and 30% of the world’s seaborne fertiliser exports come from the Gulf region.

"That will drive food prices sharply higher, particularly in lower-income countries."

Judith McKenzie, a partner at investment firm Downing, noted that the full effects of the conflict have yet to filter through the fuel supply chain to consumers.

"Oil shocks are not immediate," she said during a radio interview.

"If tensions in the Gulf ease this week, it will still take time to stabilise and inflation will rise, but the situation can be managed."

Roughly one-fifth of global oil and gas supplies normally transit through the narrow Strait of Hormuz, but traffic has largely stalled, adding upward pressure to prices.

Sean Foley, an energy markets specialist at Macquarie University, said oil prices were likely to climb further unless hostilities subside.

He added that Houthi attacks have also sparked fears that the group could disrupt shipments through the Bab al-Mandeb Strait near Yemen.

If that passage were blocked, it could affect an additional 10% of the world’s oil supply, placing "significant strain on global supply chains," Foley warned.

Andrew Lipow, president of Lipow Oil Associates, predicted that Brent crude could reach $130 per barrel in the coming weeks if threats to global energy infrastructure continue.

"My biggest concern is a broader economic slowdown," he said. "Consumers may exhaust their budgets as they face rising energy and food costs."

Brent crude was trading at approximately $72 per barrel on 27 February, one day before the US and Israel launched strikes on Iran.

By 18 March, the global benchmark had climbed to $119.50 per barrel, its highest level since June 2022.