Oil prices pared gains after briefly climbing above $100 a barrel following an announcement from US President Donald Trump that he was extending a ceasefire with Iran until Tehran submits a proposal, Reuters reports.

Brent crude futures were volatile, settling up about 3 per cent and then climbing further to rise more than 5pc to a session high of $101.15.

Prices later retreated after Trump said the ceasefire would remain in place until Iranian leaders present what he called a unified proposal and talks are concluded, though he said the US naval blockade of Iran would continue.