BERLIN, March 2 (Reuters) - German monthly retail sales unexpectedly declined in January, data showed on Friday, in a sign that private consumption may remain weak in early 2018 after failing to make any contribution to growth in Europe's biggest economy in the fourth quarter.
The volatile indicator, which is often subject to revision, showed retail sales fell by 0.7 percent on the month in real terms, the Federal Statistics Office said.
That missed the Reuters consensus forecast for a 0.9 percent rise and came after an upwardly revised drop of 1.1 percent in December.
Private consumption has been a key growth driver in recent years as consumers benefit from rising wages, record-high employment and strong job security but data published last week showed foreign trade propelled Germany's fourth-quarter expansion of 0.6 percent.
On the year, retail sales increased by 2.3 percent, missing a Reuters consensus forecast for a 3.5 percent increase.
The retail sales data came after a GfK survey published on Wednesday showed the cheerful mood among German shoppers darkened heading into March in a sign that political concerns could be weighing on a consumer-led upswing in Europe's biggest economy. (Reporting by Michelle Martin Editing by Paul Carrel)