The deal for Mozambique's offshore Area 1 is expected to close around the end of this year.
OVL, along with Oil India Ltd, had in June agreed to buy Videocon Group's 10 per cent in the same block for $2.48 billion.
Anadarko will remain the operator of Area 1 with a working interest of 26.5 per cent in the block, which is located in Mozambique's deepwater Rovuma Basin.
"OVL has signed definitive agreements on August 24 with Anadarko Moçambique Area 1 Limitada (Anadarko) to acquire a direct 10 per cent participating interest in the Rovuma Area 1 Offshore Block in Mozambique for $2.64 billion," a company statement said in New Delhi.
The acquisition is subject to the approvals of the governments of Mozambique and India, relevant regulatory approvals, pre-emption
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