The collapse in oil prices is starting to slow growth in U.S. output, OPEC said on Thursday, although the slowdown will not prevent demand for the exporter group's oil falling in 2015 to its lowest in a decade.
In a monthly report, the Organization of the Petroleum Exporting Countries (OPEC) forecast demand for the group's oil will drop to 28.78 million barrels per day (bpd) in 2015, down 140,000 bpd from its previous figure and the lowest since 2004.
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OPEC also trimmed the rate of growth in non-OPEC supply partly due to a slowdown in the U.S. shale boom.
"As drilling subsides due to high costs and a potentially sustained low oil price, production could be expected to follow, possibly late i 2015," it said.
OPEC lowered its forecast of total U.S. oil supply in 2015 by 100,000 bpd.