The total oil output from the basins was expected to rise 113,000 bpd, driven largely by increases in the Permian Basin of Texas and New Mexico, where output was forecast to climb by 63,000 bpd to about 3.7 million bpd in December, the US Department of Energy's Energy Information Administration (EIA) said.

Output was also expected to rise in each of the other basins, except for the Haynesville, where it would remain unchanged at 43,000 bpd.

US natural gas production, meanwhile, was projected to increase to a record 75.1 billion cubic feet per day (bcfd) in December. That would be up more than 1.0 bcfd over the November forecast and would be the 11th monthly increase in a row.

A year ago in December output was just 63.9 bcfd.

The EIA projected gas output would increase in all the big shale basins in December.

Output in the Appalachia region, the biggest shale gas play, was set to rise 0.4 bcfd to a record 30.4 bcfd in December. Production in Appalachia was 26.9 bcfd in the same month a year ago.

EIA said producers drilled 1,577 wells and completed 1,308 in the biggest shale basins in October, leaving total drilled but uncompleted wells up 269 at a record high 8,545, according to data going back to December 2013.

That was the most wells drilled in a month since February 2015 and the most completed in a month since March 2015, according to EIA data.