The Saudis are also significant arms buyers from both the United States and Britain, and Trump argues that those sales mean jobs. Russian Federation has also been angered by President Donald Trump's threat to pull out of a bilateral agreement to limit nuclear missile deployment. But he added that with Iranian sanctions coming into full force next month, there were no guarantee oil prices would not go higher.
"Now, we have to wait and see if this continues to spiral out of control", said Mr Gene McGillian, vice-president of market research for Tradition Energy in Stamford, Connecticut.
Last week, WTI fell below the $70 mark for the first time in a month, after the Energy Information Agency reported a larger than expected rise in USA inventories.
Speaking at an investment conference in Riyadh, Falih said OPEC and non-OPEC producers are expected to sign in December an accord to continue cooperation in world energy markets.
"If 3 million barrels per day disappear, we can not cover this volume".
Falih said he would not rule out that Saudi oil output would be 1-2 million barrels per day higher than current levels in future as oil demand growth is expected to keep rising.
Kunlun, the main official channel for money flows between China and Iran, has verbally informed clients that it will stop accepting yuan-denominated Iranian payments to China from November 1, said the sources, who include external loan agents and business officials who trade with Iran. "No one else will believe him", the Iranian minister said then.
Highlighting Iran's "steady and stable supply of oil to customers", he stressed that no country has "the capacity to provide a replacement for the Iranian oil in the world's demanding market". A lower price will help. The sanctions prohibit other nations to enter into new contracts with Iran immediately and provide a six-month period ending 4 November to wind-down existing commitments with the country, especially with Iranian oil companies.
"There are several reasons for the slide in crude oil, chief among them is it's a risk-off day across all financial markets", said Bob Yawger, director of the futures division at Mizuho Securities USA. This is the objective of the agreement: "monitor and stabilise", he said.
"If, supplies start increasing and inventories continue to build to where we get anxious about repeating the 2014 scenario then we will have the mechanism in place to reconvene and quickly re-arrange production and bring supply-demand balance and prevent inventories from growing", Mr Al Falih said.