Oil prices have extended their gains as efforts to end the US-Iran war appear stalled, with the crucial Strait of Hormuz waterway still mainly shut, keeping energy supplies from the key Middle East producing region out of the reach of global buyers.

Brent crude futures for June climbed 45 cents, or 0.4 per cent, to $108.68 a barrel as of 00:51 GMT (5:51am PKT), after gaining 2.8pc in the previous session to its highest close since April 7. The contract is up for a seventh day.

US West Texas Intermediate (WTI) crude for June rose 58 cents, or 0.6pc, to $96.96, after gaining 2.1pc in the previous session.