India's auditor has rapped the state-run Oil and Natural Gas Corp over its $2.08 billion) purchase of Russia-focused Imperial Energy group.

The government auditor said Imperial, whose main assets are in the Tomskh region of eastern Russia, has produced lower than projected output and its oil reserves had been inflated.

London-listed Imperial has been able to achieve production of only 15,803 barrels of oil per day (bpd) as against the envisaged production levels of 35,000 bpd (at the time of acquisition), the Comptroller and Auditor General said in its report tabled in parliament late on Friday,

The shortfall had caused a loss of 11.8 billion rupees ($259.8 million) on top of several billions dollars in losses stemming from unproductive exploration of assets.
The ONGC group still has "to succeed as an (energy) operator", the report said.

ONGC Videsh, the overseas arm of ONGC, acquired Imperial Energy in January 2009 for US$2.12 billion, making it the company's most expensive acquisition ever.

The ONGC group had to reduce the proven reserve size of the asset during 2009-10 by 1.53 million tonnes "indicating the inflated size of reserves estimated by the company at the time of its acquisition", the auditor-general said.

"The fact the company even now is not in a position to generate a realistic production profile and bring out an economic analysis confirms all the problems associated with these fields were not properly assessed," the report said.

Investors are already nervous about India's raft of financial scandals and analysts say the damning report could jeopardise the government's plans to sell off a five per cent stake in ONGC sometime mid-year.

The report criticising ONGC comes after the auditor last year stirred a massive controversy by saying the government's cut-rate sale of mobile licences had cost the public treasury up to US$40 billion.

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