The firm is expected to issue bonds with 5- or 10-year tenure and the deal is expected to hit the market in January after the documentation process is complete, the sources said.
"Currently borrowing in dollars is available at cheaper rate. Our purchase of assets is in dollar and in our balance sheet asset and liabilities are shown in dollars," said DK Saraf, managing director of ONGC Videsh.
Hess Corp said in September it had agreed to sell its 2.72% stake in the large Azeri, Chirag and Guneshli(ACG) group of oilfields, as well as its 2.36% stake in an associated pipeline to ONGC for $1 billion.
Indian issuers can borrow up to $750 million in markets abroad under the automatic approval route and must seek Indian central bank permission to raise more.
"If we get permission, we will raise $900 million. Otherwise it will be $750 million," said a separate source, adding that the borrowings will be made in January.