Analysts said sentiment remained weak as oil prices fell in global markets after industry data showed U.S. stockpiles of crude unexpectedly rose, starting the new month in negative territory after the largest monthly decline in two years in July.
Futures fell for the third day in NY, losing as much as 1.1 per cent to hit their lowest level since June 22, but USA government's data showed a surprise gain in nationwide stockpiles on Wednesday.
Brent for October settlement fell 34 cents to $72.05 a barrel on the London-based ICE Futures Europe exchange, after dipping $1.82 on Wednesday.
Saudi Arabia, Russia, Kuwait and the United Arab Emirates have increased production, as agreed at a meeting in June, to help to compensate for an anticipated shortfall in Iranian crude supplies once US sanctions take effect.
Crude oil prices started the trading day Thursday in negative territory, but quickly shifted into rally mode on signs that US crude oil stocks at the key storage hub in Cushing, Okla., were drying up.
In the previous week, total US inventories rose 3.8 million barrels, while supplies at Cushing fell 1.3 million barrels.
The West Texas Intermediate (WTI) for September delivery lost 0.47 USA dollar to settle at 68.49 dollars a barrel on the New York Mercantile Exchange, while Brent crude for October delivery erased 0.24 dollar to close at 73.21 dollars a barrel on the London ICE Futures Exchange.More news: Apple is officially worth more than $1 trillion
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Crude oil futures remained relatively stable in European morning trading, following yesterday's rally of more than $1/b, as the market held up against short-term bearish factors that continue to weigh on sentiment.
Oil markets have been halting further declines recently after the energy commodity fell too far, too fast on pumped-up production from OPEC, and supply constraints both within the U.S. overseas have seen oil markets quick to buy, implying that bullish oil traders, while sidelined on rising production, are remaining close at hand.
Elsewhere, oil prices may be moving on growing concerns about US-Chinese trade policies.
U.S. President Donald Trump's decision to pull out of an worldwide nuclear deal and reimpose sanctions on Iran has angered Tehran.
Trump has turned up pressure on China for trade concessions by proposing a higher 25% tariff on $200 billion of Chinese imports and China has said it will retaliate.
Crude oil costs experienced their worst monthly decline in over two years in July as a multi-year high in barrel prices broke away amidst plans by OPEC and Russian Federation to boost production limits.
During the first half of the year, China imported an average of 330,000 Bpd from US producers. "This could severely dent the competitiveness of USA oil and derivatives in the Chinese market", said Abhishek Kumar, senior energy analyst at Interfax Energy.