Sales of US existing homes rebounded sharply in December from a November slump, scoring the biggest one-month gain on record, the National Association of Realtors said Friday.

Existing-home sales jumped 14.7 percent to an annual rate of 5.46 million units in December from 4.76 million in November.

December sales were up 7.7 percent from a year ago.

The rebound came after November sales slumped to the slowest pace in 19 months, due in part to new mortgage disclosure rules that delayed closing times on contracts, the NAR said.

"While the carryover of November's delayed transactions into December contributed greatly to the sharp increase, the overall pace taken together indicates sales these last two months maintained the healthy level of activity seen in most of 2015," said Lawrence Yun, NAR chief economist, in a statement.

For all of 2015, sales of single-family homes, condominiums and other types of housing reached 5.26 million units, the strongest performance since 2006 when 6.48 million units were sold.

All four major regions had large gains in December, led by the South and West.

"The prospect of higher mortgage rates in coming months and warm November and December weather allowed more homes to close before the end of the year," Yun added.

Sales of single-family home, the largest sector in the market, jumped 16.1 percent in December to 4.82 million units.

The median price for all housing types rose year-over-year for the 46th straight month, to $224,100, a gain of 7.6 percent from a year ago.

Inventory on the market tightened further. At the end of December, there were 1.79 million existing homes for sale, down 12.3 percent from November and 3.8 percent from a year ago.

"Although some growth is expected, the housing market will struggle in 2016 to replicate last year's seven percent increase in sales," Yun said.

"In addition to insufficient supply levels, the overall pace of sales this year will be constricted by tepid economic expansion, rising mortgage rates and decreasing demand for buying in oil-producing metro areas."