Russia's industrial output grew by 3.7 percent in May year-on-year, above an official forecast of 2.1 percent, the Federal State Statistics Service (Rosstat) said Monday.

Earlier, the Ministry of Economic Development made the forecast in April. The ministry also forecasted the country's industrial output would reach 3.1 percent in 2012.

According to Rosstat, in the first five months, Russia's industrial output grew by 3.4 percent compared with the same period of 2011.

Analysts believed the industrial output growth was mostly thanks to the growth in the country's processing industries, which saw a 7-percent growth in May, compared to April's 3.6 percent.

Besides, a 0.3-percent overall decline was reported in raw materials production in May due to a sharp decline of natural gas extraction, which fell by 10.8 percent against May 2011.

Crude oil production remained flat in May.

In 2011, Russia's industrial output grew 4.7 percent.