Oil prices fell on Monday as the start to US sanctions against Iran's fuel exports was softened by waivers that will allow some countries to still import Iranian crude, at least temporarily.
Front-month Brent crude futures were at $72.39 per barrel on Monday, down 44 cents, or 0.6% from their last close, CNBC reported.
US West Texas Intermediate crude futures were down 53 cents, or 0.8%, at $62.61 a barrel. Brent has lost more than 16% in value since early October, while WTI has declined by more than 18% since then.
This came as traders cut their bullish wagers on crude futures to a one-year low by the end of October, the fifth consecutive cut during a month when prices posted their largest drop since July 2016, data showed on Friday.
Prices have been coming under pressure since it became clear that Washington was allowing several countries to continue importing crude from Iran despite the sanctions, which officially started on Monday.
The United States said on Friday it will temporarily allow eight importers to keep buying Iranian oil when it re-imposes sanctions, aimed at forcing Iran to curb its nuclear, missile and regional activities.
Washington has so far not named the eight, referred to as "jurisdictions", a term that might include Taiwan which the United States does not regard as a country.
China, India, South Korea, Turkey, Italy, the UAE and Japan have been the top importers of Iran's oil, while Taiwan occasionally buys Iranian crude, although it is no major buyer.
Oil markets have been preparing for the sanctions for months.
"Iranian exports and production had been declining steadily...Iranian exports show a decline of more than 1 million barrels per day as of October from May," said Edward Bell of Emirates NBD bank.
On the demand side, Bell warned that consumption may be slowing due to an economic slowdown, as seen in a sharp drop in refining profits.
"Sagging refining margins at a time of weak crude prices sends a very telling message to us that demand is underperforming," he said.
A slowdown in demand would come just as output is rising.