The global crude oil market is keeping an eye on how quickly U.S. oil production falls during an era of lower prices, OPEC said in its latest market report.

The Organization of Petroleum Exporting Countries said it expected production from non-member states to grow by about 160,000 barrels per day next year, a downward revision of about 110,000 bpd from the previous report.

The global market is skewed toward the supply side as weak European and Asian economic growth is keeping demand suppressed. Crude oil prices are down more than 50 percent from last year, leaving energy companies with less cash to invest in exploration and production.

"In North America, there are signs that U.S. production has started to respond to reduced investment and activity," OPEC said in its monthly market report. "Indeed, all eyes are on how quickly U.S. production falls."

A report last week from the U.S. Energy Information Administration said seasonal factors offshore and weak economics onshore are expected to lead to a decline in U.S. crude oil production. In a short-term market report, EIA said total crude oil production will decline 4.3 percent from expected full-year 2015 levels to 8.8 million barrels per day by 2016.

EIA forecasts were revised down by 100,000 bpd from August.

OPEC in its market report said world oil demand growth is expected to be around 1.46 million bpd for 2015, an upward revision of about 84,000 bpd. Lower oil prices are the main driver of demand and modest economic growth.

"At the same time, U.S. oil production has shown signs of slowing," OPEC said. "This could contribute to a reduction in the imbalance of oil market fundamentals, however, it remains to be seen to what extent this can be achieved in the months to come."