Oil prices traded lower on concerns over the global oil oversupply and the slowdown in the Chinese economy. The National Bureau of Statistics said on Monday that China's economy expanded 6.9% in the third quarter, beating expectations for a 6.8% gain, after a 7.0% in the second quarter. It was the weakest growth since 2009.
China's industrial production increased 5.7% on year in September, missing expectations for a 6.0% rise, down from a 6.1% gain in August.
Comments by Iran's Oil Minister Bijan Zanganeh added to concerns over the global oil oversupply. He said on Monday that Iran would raise its oil production by 500,000 barrels a day after the nuclear deal is implemented.
Zanganeh also said that he does not expect the Organization of Petroleum Exporting Countries (OPEC) to cut its oil production at its next meeting on December 04. Iran's oil minister noted that the OPEC should lower its oil output to boost prices to a range of $70 to $80 a barrel.
Saudi Arabia's commercial crude oil inventories climbed to 326.6 million barrels in August from 320.2 million barrels in July, according to the Joint Organisations Data Initiative (JODI) data. It was the highest level since 2002.
According to the JODI data, Saudi Arabia' oil production fell to 10.27 million barrels a day in August from 10.36 million in July. Saudi Arabia said that its oil production totalled 10.23 million barrels a day in September.
Meanwhile, the number of the U.S. rigs declined again. The oil driller Baker Hughes reported on Friday that the number of active U.S. rigs declined by 10 rigs to 595 last week. It was the seventh consecutive decrease and the lowest level since the week ending July 23, 2010.
WTI crude oil for November delivery declined to $46.65 a barrel on the New York Mercantile Exchange.
Brent crude oil for November decreased to $48.90 a barrel on ICE Futures Europe.