Brent crude lost 37 cents to $84.61 per barrel by 1200 GMT on Tuesday after reaching a four-year high of $85.45 in the previous session.
Brent has risen by around 20 percent from the most recent lows in August.
Worldwide oil benchmark, Brent crude, extended its gains on Monday, rising to its highest level of $84 per barrel since November 2014.
Futures rose as much as 0.4 percent 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.
The US President Donald Trump reviewed on Saturday in a phone call with Saudi King Salman bin Abdulaziz Al Saud the oil supply for stability of the market, Saudi Press Agency reported. It should be noted that the call to reduce oil prices comes from a major exporter, as United States oil production is booming at record levels with exports surpassing most OECD countries.
"Oil prices continue to climb, supported by the nearing Iran embargo and related supply concerns", said Norbert Ruecker, head of commodity research at Swiss bank Julius Baer.
USA sanctions are due to begin on November 4, and analysts are seeing a potential shortage of spare production capacity in the short-term, which might prompt huge storage drawdowns.
"Our oil analysts believe there is now a growing risk it (crude) could touch $100 per barrel", HSBC said in its fourth-quarter Global Economics outlook.
Oil has risen to the highest in nearly four years in London after OPEC showed little enthusiasm for raising output despite President Donald Trump's demand for lower prices. Analysts say prices likely will go higher as American sanctions on Iran resume in November.
Soaring crude prices and weak emerging market currencies may erode economic growth.
"Even if they (Saudi Arabia) wanted to bend to President Trump's wishes, how much spare capacity does the Kingdom have?" he asked.