U.S. West Texas Intermediate (WTI) crude futures were at 73.57 dollars a barrel.
Worldwide benchmark Brent crude futures for December delivery dropped 0.6 percent to $84.43 per barrel, hovering just below its highest since November 2014 of $85.45-peak hit on Monday.
Futures were little changed in NY after closing Monday at the highest since November 2014.
Early survey data by Reuters shows that although OPEC was pumping in September at its highest level so far this year, a 100,000-bpd plunge in Iran's production curtailed the supply boost from the cartel last month.
Jabouley said at current price, oil producers will start to pump up their production capacity and flood the market with the commodity. Many analysts say the Organization of the Petroleum Exporting Countries (OPEC), of which Iran is a member, will struggle to replace export falls from Iran.
"There is concern in the market that the loss of barrels from Iran and Venezuela is not going to be made up for through extra supplies from particularly Saudi Arabia and Russian Federation", said Gene McGillian, manager of market research at Tradition Energy.
Growing uncertainties over global oil supply have sent prices soaring in NY to their highest level in almost 4 years.
Oil market sentiment was lifted by a last-gasp deal to salvage NAFTA as a trilateral pact between the United States, Mexico and Canada. However, China's Sinopec 600028.SS is halving loadings of crude oil from Iran this month, in a sign that pressure from Washington is having an effect.
"Even if they (Saudi Arabia) wanted to bend to President Trump's wishes, how much spare capacity does the Kingdom have?" he asked. Money managers are positioning for a shortage of Brent and Brent-linked oil grades, as the USA sanctions on Iran are expected to remove more than 1 million bpd-some say even more than 1.5 million bpd or as much as 2 million bpd-of Iranian oil from the market.
With crude prices soaring and many currencies in emerging markets, including India's rupee and Indonesia's rupiah declining, analysts warn that economic growth may be eroded.