Cairn wants the stakes that its different subsidiaries, including those registered abroad as well as showpiece Rajasthan oilfields, hold in oil and gas properties, to be transfered into one India-based company.
Since ONGC is partner in six of those properties, Cairn procedurally sought a no-objection from ONGC, but the state-run oil major has so far not agreed to the proposal, sources privy to the development said.
The restructuring is separate from London-listed mining group Vedanta Resources' $9 billion buyout of Cairn India.
While the Vedanta deal, where Edinburgh-based Cairn Energy Plc is selling 40 per cent of its interest in Cairn India, was announced in August, 2010, the restructuring began in 2009.
Two top ONGC officials, however, when contacted, could not reason why the consent was withheld.
The restructuring, which was approved by the board of Cairn India and boards of its subsidiaries in December, 2009, has no bearing on the Vedanta deal, sources said.
In December, 2009, Cairn got no-objection certificates for the restructuring from the National Stock Exchange and Bombay Stock Exchange, where it is listed.
The company's shareholders also approved the scheme in February, 2010.
In April last year, the Chennai high court nodded the restructuring and Bombay high court sanctioned the scheme in June, 2010.
But ONGC, which holds up to 90 per cent interest in the Cairn properties, has not given its no-objection certificate yet, they said.
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