President Donald Trump suggested on Sunday that the United States (US) could stay in Iran and “keep the oil”, drawing a parallel with a US push to take control of a fifth of Venezuela's vast oil reserves.

On a trip to Ireland for meetings and to watch golf, he reiterated that he still expected the Iran war to end this year, possibly just after midterm elections due in the US in November.

Speaking at the Irish Open golf championship, Trump added that the price of gasoline would “drop like a rock” once the Iran war ended.

Turmoil in West Asia has roiled oil markets, with oil traders expecting prices to rise again on Monday after an attack on a Saudi oil pipeline.

Trump said that he would only make the “right deal” and wouldn't do one that was “no good”, adding that Iran was “calling constantly” for peace talks — an assertion that Tehran has dismissed in the past.

But the president also introduced another option: stay engaged with Iran. He drew a parallel with the US deal in Venezuela, announced in August.

“We'll ultimately get out (of Iran), unless we decide to stay and keep the oil like Venezuela,” Trump said, adding that the US revenue from Venezuela has “paid for the war many times.”