Oil prices surged more than 6% on Wednesday, reaching a two-week high, after US President Donald Trump declared that the memorandum of understanding to end the conflict with Iran was "over" and said he no longer wished to engage with Tehran. The comments revived fears of disruption to Middle East oil supplies, particularly through the Strait of Hormuz, a shipping route that carried around a fifth of global energy supply before the war began in late February.

Brent crude rose $4.57, or 6.16%, to $78.73 a barrel, while US West Texas Intermediate climbed $4.23, or 6.01%, to $74.67, both at their highest since 22 June. The rise followed a roughly 3% gain on Tuesday after the US revoked the licence authorising sales of Iranian crude. A Pakistan-brokered agreement last month had provided a 60-day negotiating window, but it came under strain after fresh US strikes on Iran — a response to Iranian attacks on three commercial vessels — and Iran's Revolutionary Guards said they had targeted US military sites in Bahrain and Kuwait. At least four tankers turned back from the strait, and analysts suggested prices nearer $80 a barrel better reflected current fundamentals, while China moved to resume refined fuel exports.