PARIS French cosmetics giant L'Oreal (OREP.PA) on Thursday said Western Europe was being held back by a "very difficult market in France", posting a 4.3 percent rise in second-quarter sales, marginally below forecasts.

However, the maker of Biotherm cream and Armani perfume said sales growth was accelerating as expected in North America and it would continue to outperform the market globally throughout the year.

A Reuters polls of 12 analysts forecast L'Oreal's total second-quarter sales growth would reach 4.61 percent.

​The group, which is holding a conference call on Friday at 0700 GMT, said it expected to continue to outperform the market globally throughout the year.

In advance of the call, the French cosmetics giant also commented on two impairment charges. The group said the performance of two acquisitions, China's Magic Holdings face mask provider and sonic skin care Clarisonic, was below expectations and led to a 447 million euro impairment charge in its first half results.

L'Oreal took a writedown of 213 million euros ($236 million) on Magic Holdings which it bought for $840 million two years ago and wrote down 234 million euros on the value of Clarisonic which it took on in 2011.