Private sector in the U.S. added 257,000 jobs in December, according the ADP report on Wednesday. November's figure was revised down to 211,000 jobs from a previous reading of 217,000 jobs.

Analysts expected the private sector to add 192,000 jobs.

Services sector added 234,000 jobs in December, while goods-producing sector added 23,000.

"Strong job growth shows no signs of abating. The only industry shedding jobs is energy. If this pace of job growth is sustained, which seems likely, the economy will be back to full employment by mid-year," the Chief Economist of Moody's Analytics Mark Zandi said.

Official labour market data will be released on Friday. Analysts expect that U.S. unemployment rate is expected to remain unchanged at 5.0% in December. The U.S. economy is expected to add 200,000 jobs in December, after adding 211,000 jobs in November.