Global oil prices have shot up more than 5% after US President Donald Trump said America had seized an Iran-flagged cargo ship.
It comes following a volatile weekend in which Iran announced on Saturday it was once more closing the Strait of Hormuz to commercial ships and would target any that approached it.
That came just a day after Iran said the Strait would be "completely open" to commercial vessels for the remained of the agreed ceasefire, which temporarily eased markets and caused the oil price to fall 9%.
But following Trump's announcement about the seizure of an Iran-flagged ship, the global benchmark oil price rose by 5.4% at $95.27 (£70.62) a barrel, while the US benchmark was 5.9% higher at $88.79, the BBC reports.
The US President also said his representatives will be in Pakistan today for negotiations led by Vice President JD Vance,
However, according to Iranian state media, the country has "no plans for now to participate" in the talks.
Officials have yet to clarify the country's position.
Analyst Saul Kavonic, from financial services firm MST Marquee, told the BBC: "Oil markets continue to gyrate in response to oscillating social media posts by the US and Iran, rather than the realities on the ground which remain challenging for oil flows to resume in a rapid fashion.
"This is all part of negotiations, physically playing out in real time on the Strait of Hormuz."
FSTE100
The UK's flagship share index, the FTSE 100, was up 45 points at 10,625 shortly after opening this morning.
Brent crude oil futures were down 1.41% trading at $95.26 a barrel.
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