The comments come just days after Trump complained that Washington was "subsidising" Saudi Arabia's military, echoing similar jibes at European members of the North Atlantic Treaty Organisation alliance.
Iran accused Saudi Arabia and Russian Federation on Wednesday of breaking OPEC's agreement on output cuts by producing more crude, adding that the two countries would not be able to produce enough oil to make up for a reduction in Iranian exports. If the White House was informed about the secret private deal, it didn't seem to resolve Trump's concerns.
Speaking at the United Nations General Assembly in NY last month, Trump accused OPEC members of "ripping off the rest of the world". It demonstrates that the Saudis do not want to be perceived as doing Trump's bidding.
One analyst said the Saudi plan to pump more would not change much.
Oil prices have been climbing as buyers have already started steering clear of Iran before the implementation of USA sanctions starting November 4.
Brent crude LCOc1 rose $1.49, or 1.8 percent, to settle at $86.29 a barrel, after hitting $86.74, its highest since October 30, 2014. Was that a deliberate strategy by the Saudis to leak the details to the press in order to inform the market?
OPEC's largest producer is now pumping about 10.7 million barrels a day, Energy Minister Khalid Al-Falih told reporters in Moscow on Wednesday. "We've increased production quite significantly".
Nevertheless, the White House still does not appear to be completely mollified.
"When you have wealthy countries like Saudi Arabia, like Japan, like South Korea, why are we subsidising their military?" asked Trump, who pushes an aggressive "America first" policy on trade. "You have to pay for your military, you have to pay'". "But we don't get what we should be getting", he said at a rally in West Virginia.
Speaking at a campaign rally in Mississippi, Trump said, "I love the king, King Salman, but I said, 'King, we're protecting you".
The presence of the United States military in Saudi Arabia, home to the two holiest sites in Islam - Mecca and Medina - was strongly objected to by most of the world's Muslim population, according to opinion polls published by Gallup in 2009.
"We protect Saudi Arabia - would you say they're rich?"
It remains to be seen if Trump can convince the Saudis to take a more aggressive line, although it should be noted that Saudi Arabia's decision to increase production by 300,000 bpd from August levels is not trivial. "OPEC is not trying to manipulate the price, it's trying to bring the market to balance", he told CNBC.