A group of OPEC and non-OPEC producers have been voluntarily withholding supplies since January 2017 to tighten markets, but with crude prices up by more than 40 per cent since then and markets significantly tighter, there has been pressure on producers to raise output.
Oil prices rose on Tuesday amid looming United States sanctions against Iran's petroleum industry, despite efforts by Washington to get other major suppliers to make up for the expected disruption.
Oil traders were also watching the progress of category 4 Hurricane Florence, which is expected to make landfall in the U.S. by Friday.
"Oil cut earlier losses and rose towards its highest level this year on Wednesday, after a drop in USA crude inventories and as the prospect of the loss of Iranian supply added to concerns over the delicate balance between consumption and production". Eyes will be on Iranian oil import data from China and India who typically import around 500-700k barrels.More news: Turkey stuns market with massive interest rate hike
China has said that it would not stop buying Iranian oil, but Beijing is also said to have agreed not to increase its oil purchases from Iran.
"South Korea bought 194,000 bpd from Iran in July", OilPrice said.
Gordon Gray, HSBC's global head of oil and gas equity research, said there were "real risks" that Brent could hit $100 a barrel. Oil production has been hit by attacks on oil facilities and blockades, though past year it partially recovered to around one million barrels per day.
Total Iranian oil shipments for September-although we're just one third into the month and more tankers could leave later in September-slumped to 1.3 million bpd through September 13, compared to just above 2 million bpd in August, when Iranian exports started to fall noticeably, according to Bloomberg's data.More news: Hurricane Florence could 'kill a lot of people'
S&P global Platts said OPEC, in a report, indicated demand for the organization's own crude oil in September will be nearly 1 million bpd more than the level produced in August.
In 2018, demand for OPEC crude is expected at 32.91 million bpd, with demand for the second half to average 33.50 million bpd, the monthly market report showed.
But it said rising demand could also be checked.
The United States and China have imposed a series of tariffs on each other's goods since May that have unnerved equity markets, while a rising US dollar has put emerging market currencies under pressure, raising the energy bill for some of the world's largest oil importers.More news: Aung San Suu Kyi defends imprisonment of Reuters journalists
WTI was pushed over $70 during the previous session due to falling crude inventory and production levels.