BP\'s Russian joint venture TNK-BP closed a deal to buy a 45 percent stake in an oil and gas deposit in Brazil from the local firm HRT O&G, TNK-BP said in a statement on Tuesday. \"The Brazilian National Agency of Petroleum, Natural Gas and Biofuels approved ... the concession rights and obligations transfer from HRT O&G to TNK Brasil regarding a 45 percent participating interest in 21 blocks located in the Solimoes Basin, onshore Brazil,\" TNK-BP said in a statement. The 21 oil and gas exploration blocks covering an area of about 48,500 square kilometers are located in the Amazon\'s Solimoes basin. TNK Brasil will pay $1 billion to HRT by five tranches within two years. The expected reserves of the blocks are estimated at 783 million barrels of oil equivalent under an audit report of Degolyer & MacNaughton. Production at the Solimoes Basin is to be launched this year. \"We are pleased that the Brazilian authorities have approved our agreement with HRT and this significant deal is now closed. Our international operations play an important role in our portfolio,\" TNK-BP CEO Mikhail Fridman was quoted in the statement as saying.