MOSCOW, Aug 6 (Reuters) - Vimpelcom, Russia's third-biggest mobile operator with assets in Italy and several emerging markets, said on Wednesday its second-quarter net profit fell 83 percent from a year ago to $100 million, missing analysts expectations.

Revenue fell 11 percent to $5.07 billion and earnings before interest, taxation, depreciation and amortisation (EBITDA) declined 14 percent to $2.08 billion, slightly below forecasts.

The company said the results were impacted by continued market weakness in Italy and underperformance and economic slowdown in Russia, Ukraine and Pakistan.

Russia's No.3 operator, in which Russia's Alfa Group and Norway's Telenor are the biggest shareholders, also confirmed annual targets. In May, it said it expected "low to mid single digit" declines in sales and EBITDA this year.

Analysts had expected it to report net profit of $270 million, revenues of $5.10 billion and EBITDA of $2.12 billion for the second quarter.

(Reporting by Maria Kiselyova; Editing by Anupama Dwivedi)