"We have asked ONGC to hire legal experts with knowledge of both Russian and US law and appoint international consultants specialising in mergers and acquisitions for studying the implications involved in taking stake in Yuganskneftegaz (Yugansk)," a top official in the ministry of petroleum and natural gas said.
Russian oil firm Rosneft has offered ONGC a 15 per cent stake in Yugansk after Moscow effectively nationalised it through an auction last month to collect unpaid tax dues.
Yukos, which had got a bankruptcy court in the US to stay the auction, has threatened ONGC with legal action if it acquires stake in Yugansk and would seek 20 billion dollars in damages.
Russia, however, ignored the US court ruling and went ahead with the auction, which ultimately went in favour of Rosneft.
Yuganskneftegaz produces one million barrels per day of oil or over 60 per cent of Yukos output.
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The official said ONGC was talking to Rosneft and Russian authorities for the stake. "ONGC would do a proper due diligence before deciding on the stake."
"We are not talking to Yukos... We are evaluating an offer (from Rosneft) for 15 per cent stake in Yugansk," he said downplaying Yukos' threat of legal action.
"We are discussing an offer made by a sovereign government and its legally established company," he added.