US crude output has grown by over 10% since mid-2016 but didn't let oil prices to surge.
A source also told Reuters that seven million barrels is roughly two days' worth of oil imports into Japan, the world's fourth biggest importer.
High US gasoline stocks have fed concern about demand in the US, where consumer spending expectations hit a three-year low last month and vehicle sales have fallen year-on-year for four months.
The Organization of the Petroleum Exporting Countries and 11 non-cartel members in late November agreed to slash production for six months by 1.8 million barrels a day.
The Opec report confirmed that United States oil and gas companies have already stepped up activities in 2017 amid a recovery in oil prices.
The two biggest producers participating in the cuts, OPEC's Saudi Arabia and non-member Russian Federation, both signaled willingness on May 8 to extend the deal.
TOKYO: Oil futures rose in Asian trading on Wednesday after Reuters reported Saudi Arabia would cut supplies to the region as OPEC battles against rising USA output that is threatening to derail its attempts to end a sustained global glut in crude.
WTI for June delivery traded down more than 1% at around $45.90, after touching a high of $46.78 earlier Tuesday morning.
The IEA now sees global oil demand growth of 1.3 million barrels a day, lower than the growth of 1.6 million seen in 2016 and the 2 million recorded in 2015.
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In the report, OPEC pointed to continued high compliance by its members with the supply deal and said oil stocks in industrialized nations fell in March - although they are still 276 million barrels above the five-year average.
The chart pattern suggests June WTI crude oil is still trying to form a bottom so if it breaks, we're likely to see further consolidation.
"As long as you've got those builds in gasoline, it is going to be hard for crude oil to rally", said Olivier Jakob, energy market strategist at Petromatrix in Zug, Switzerland.
International Brent crude futures were at $50.46 a barrel at 4.38am GMT on Thursday, up 24c, or 0.5%, from their last close.
"U.S. crude oil production is now solidly above 9.3 million barrels per day with more to come, and refined product, especially for gasoline, is oddly weak", John Kilduff, partner at hedge fund Again Capital in NY, told Reuters. U.S. crude oil inventories fell 1% week-over-week, but rose 2.6% year-over-year.
Saudi Arabia's energy minister Khalid al-Falih said on Monday he expected the output deal to be extended to the end of the year or possibly longer.
US crude stocks fall 5.2 million barrels to lowest since February.
OPEC and the other participating producers are scheduled to meet on May 25 in Vienna, Austria, to decide whether to extend the cuts and, potentially, agree a deeper reduction.