Oct 14 (Reuters) - Indian state-run explorer Oil and NaturalGas Corp said its overseas arm has agreed to buy anadditional 12 percent stake in a Brazilian oil block fromBrazil's Petrobras for $529 million.
Petrobras had earlier agreed to sell its 35 percent stake inthe block to China's Sinochem Group for $1.54 billion, but thedeal was subject to pre-emption rights of ONGC and Royal DutchShell.
Shell is the operator of the block with a 50 percent stake,while ONGC already owns 15 percent of the block.
Shell and ONGC Videsh served a pre-emption notice on Sept.17 to jointly acquire the 35 percent stake, ONGC said in astatement to Indian stock exchanges on Monday.
Reuters last month reported that the companies were planningto exercise their pre-emption right on the stake.
