US President Donald Trump said close ally Saudi Arabia and its king would not last "for two weeks" without US military support at a rally in Mississippi on Tuesday, reports Al Jazeera.
"We protect Saudi Arabia. Would you say they're rich? And I love the king, King Salman. But I said 'King - we're protecting you - you might not be there for two weeks without us - you have to pay for your military,'" the president said to cheers at the rally.
Trump did not say when he made those remarks to the Saudi monarch, but they come amid increasing oil prices in the US.
Saudi Arabia is the world's top oil exporter and the de facto leader of the oil-producing bloc, OPEC, which has been criticised by Trump for high oil prices.
Trump called King Salman on Saturday to discuss efforts to maintain supplies to ensure oil market stability and global economic growth, according to Saudi state news agency SPA.
Saudi Crown Prince Mohammed bin Salman travelled to Kuwait last weekend to speak with Kuwaiti Emir Sheikh Sabah al-Ahmad al-Jaber Al Sabah, reportedly about increasing oil production. No further developments have surfaced from the Kuwait meeting but media reports said the Gulf crisis was also on the agenda of the talks.
Speaking at the United Nations General Assembly in New York last month, Trump said OPEC members were "as usual ripping off the rest of the world".
Oil prices are on the rise. A barrel of oil currently costs about $75, continuing a steady increase over the past year. The price per barrel was around $50 in October 2017.
The average cost of a gallon (3.78 litres) of petrol in the US was three dollars in May, according to AP. Despite the harsh words, the Trump administration has had a close relationship with Saudi Arabia, which it views as a bulwark against Iran's ambitions in the region.
Qatar has denied the allegations. "We defend many of these nations for nothing, and then they take advantage of us by giving us high oil prices. Not good. We want them to stop raising prices, we want them to start lowering prices," Trump said.