MILAN (Reuters) -Revenues at Italian luxury outerwear maker Moncler fell 3% at constant exchange rates in the third quarter, slightly more than analysts had anticipated, with weakness spread across all its main markets.

Luxury groups have been struggling with tighter consumer spending in recent quarters, especially in China. Kering last week reported a larger than expected 16% drop in quarterly sales on a comparable basis.

Total revenues at Milan-based Moncler, known for its puffer jackets, totalled 635.5 million euros ($686 million) in the July-September period, against analysts' consensus forecast of 645 million euros, according to company-provided data.

Kering's rival LVMH in September invested in Moncler, originally a mountain sports brand born in the French Alps, by buying a 10% stake in Double R, the investment vehicle which owns 15.8% of Moncler.

Sales of the group's main Moncler brand totalled 532 million euros in the quarter, down 3% at constant currencies year-on-year, hit in particular by weakness in wholesale sales.

"The wholesale channel in the most important quarter for this channel [reflects] challenging market trends and efforts to improve the quality of the distribution network," it said.

Sales of the Moncler brand fell 2% year-on-year in Asia Pacific, its biggest market. They dropped 3% in Europe, the Middle East and Africa and fell 6% in the Americas.

"Our sector is going through a volatile phase, with more complex macroeconomic conditions which are impacting consumer confidence in various markets," CEO Remo Ruffini said in a statement.

Direct-to-consumer sales of the Moncler brand held steady across the Atlantic while they were negatively affected by tourist flows in Europe.

The group also owns the smaller Stone Island brand whose sales fell 4% at constant currencies in the period.

($1 = 0.9263 euros)