USA crude imports from Saudi Arabia reached 1.1 million barrels per day last month, a sixteen-month high.
US West Texas Intermediate (WTI) crude was up 15c, or 0.2%, at $72.07 a barrel by 2.55am GMT on Wednesday, having settled up 14c.
The National Iranian Oil Company announced that Tehran is resurrecting an oil exchange it used to sell oil during a last round of global sanctions four years ago, before most sanctions were lifted under Iran's 2015 nuclear deal in exchange for curbs on Iran's nuclear activities.
Market participants also said USA crude prices were being pressured by recent stock builds at Cushing, Oklahoma, the delivery point for WTI, where inventories have risen for three straight weeks.
U.S. crude stocks rose 6.5 million barrels last week, the fourth straight weekly build, as exports were down to 1.8 million barrels per day, the U.S. Energy Information Administration said, in a report analysts characterized as bearish.
Iran became India's second biggest oil supplier during the first quarter (April-June) of the current fiscal, with OMCs opting for the heftier discounts offered by the Iranians, who thus replaced Saudi Arabia in this position, according to official data.
Weak U.S. gasoline margins RBc1-CLc1 and growing U.S. shale output could also cap gains in crude prices, market participants said.
I was on CNBC Asia on Sunday evening as oil prices jumped higher, discussing how the disappearance of Jamal Khashoggi was unlikely to impact energy flows between the US and Saudi Arabia.
Oil is a globally-priced commodity, subject to the outsized influence of Saudi Arabia, its fellow OPEC member countries and other OPEC+ petrostates like Russian Federation. He also assured of increased oil production in a month.
A claim by the United States that it aims to reduce Iran's oil exports to zero is a "political bluff", the head of the state-run National Iranian Oil Company was quoted as saying. -China trade dispute on the global economy.
Since the oil embargo of the 1970s, Saudi Arabia has avoided threats to use its "oil weapon" in diplomatic affairs, insisting that it favors stable markets and separates oil and politics.
Oil prices continued to fall yesterday after USA crude inventories rose more than expected.
"So far the oil market is withstanding the verbal war and though prices are slightly higher. they are a good $5 below the peak last week", said City Index analyst Fiona Cincotta.