Brazilian state oil giant Petrobras said Monday it had sold Shell and India's ONGC Videsh its 35 percent stake in the Parque das Conchas offshore project for $1.636 billion. Petrobras said the deal followed through on an August agreement with Anglo Dutch Shell and ONGC Videsh, the overseas unit of India's biggest oil explorer, to sell off its stake in the "BC-10" zone, comprising five fields located in the south-east Campos Basin area. The deal was approved by Brazilian regulatory authorities. "Shell and ONGC Videsh have exercised their pre-emption rights for the retrospective acquisition of 23 percent (for Shell) and 12 percent (for ONGC Videsh) of the Petrobras stake," the Brazilian giant said in a statement. The Parque das Conchas blocs produced an average of 8,600 barrels per day in 2013, Petrobras added. Last month Petrobras sold off its Peruvian subsidiary to China's CNPC for $2.6 billion as part of a $9.9 billion program of divestments. The company wants to concentrate its 2013-2017 plans on tapping huge deepwater 'pre-salt' deposits off the country's Atlantic coast. Though gearing up for the pre-salt bonanza -- the deposits buried beneath several kilometers of ocean, bedrock and hot salt beds may hold up to 100 billion barrels of high-quality recoverable crude -- Petrobras has seen its share price buffeted. Its price has slumped 34 percent in 2013 over production falloffs and also a government policy of subsidizing fuel, hitting the firm's profitability. The fall off has seen the oil giant's market capitalization slide from $124.7 billion to $90.5 billion.