The forecasts from nine local and foreign economists ranged from 6.3 percent to 6.9 percent, and is slower then the 7.7 percent growth in August 2011.

Growing domestic demand continues to fuel the construction, retail and service sectors, even as the Andean country's traditional economic engine - minerals exports - suffer from slumping world prices.

Demand for cement - an indicator of growth in construction - rose 17.5 percent in August over the same month last year, according to the government statistics agency, while growth in the mining and hydrocarbons sector slowed to just 0.56 percent, down from 4.21 percent in July.

Peru is among the world's top exporters of gold, silver, copper, zinc and tin, but declining export earnings for minerals have led the central bank to trim its view for the full-year 2012 trade surplus to $3.5 billion from $6.7 billion.

Peru's Central Bank President Julio Velarde said in late September that growth in August would be slower than in July when Peru's economy posted a 7.21 percent expansion.

Official figures will be released on Monday.

Peru is expected to post growth of 6 percent this year, below the expansion of 6.9 percent last year, but still likely one of the fastest paces of economic growth in Latin America.