WASHINGTON (AFP) - The number of Americans filing for US unemployment insurance benefits jumped to a nearly six-month high last week during the Christmas holiday season, the Labour Department reported on Thursday.

Initial jobless claims rose by 20,000 to 287,000 in the week ending Dec 26.

That marked the highest level of new claims, a sign of the pace of layoffs, since the first week of July.

But claims overall have held below 300,000 since early March, amid moderate economic growth and steady job creation that pushed the unemployment rate to 5 per cent in November, a seven-year low.

The four-week moving average, which helps to smooth weekly volatility, rose by 4,500 to 277,000 last week. A year ago it was 287,750.

The Labour Department said there were no special factors impacting the data.

"Despite the modest rise in initial claims towards year-end, both initial and continuing jobless claims improved considerably in 2015 and both series remain at or near their lowest levels since the early 1970s," said Mr Rob Martin at Barclays Research.

"These data indicate that, at least from the separations side, the labour market remained strong to the very end of the year."