Melbourne/Washington | Oil prices have recorded their biggest weekly gain this year as markets brace for a potential Israeli strike on Iran, with economists warning petrol could jump 50¢ per litre to levels not seen since Russia’s invasion of Ukraine.

Brent Crude spiked 5 per cent to $US77.62 a barrel, and could rise to $US120 if Israel retaliates against Tehran’s missile strikes by targeting Iranian oil fields. If oil reached those levels, it would add $18 to the weekly household petrol bill.