The auction process remains unclear in some important respects, starting with the status of the potential bidders. Acwa, a Saudi-based power plant developer in which the government holds a minority stake, is unaware it has made the shortlist for the auction, according to one person familiar with the matter. The company would be keen to take part in a clear process, the person added.
CGN Meiya, an independent power producer, declined to comment on whether it had made the shortlist, saying only that it was always looking for high-quality projects consistent with its development plans. Nebras, an energy-focused investment vehicle set up by the Qatari government last year, was unavailable for comment. Tenaga Nasional, Malaysia's main electricity generator, declined to comment.
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Doubts also remain over exactly how much of the energy assets are up for sale. While it was originally suggested foreign buyers would be restricted to maximum holdings of 49 per cent, some people familiar with the process say overseas companies may now be offered majority stakes.
That would further boost potential foreign buyers, whose hands have already been strengthened financially because the Malaysian ringgit has fallen by more than a quarter against the dollar in the past 13 months. All bidders also know that 1MDB needs to make the sale urgently as part of its attempt to control a debt burden that has ballooned above $11 billion.
A cut-price sale to a foreign buyer could jar with the nationalist rhetoric of factions of Mr Najib's United Malays National Organisation, which has grown increasingly strident as the pressure on the prime minister over 1MDB has risen. Umno, which draws most of its support from the country's Malay majority, is facing the most serious threat yet to the political dominance it has enjoyed since Malaysia's independence in 1957.
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Mr Najib is embroiled in a spreading controversy over the international dealings of 1MDB, including over bond issues linked to the acquisition of some of the energy assets. The prime minister has faced calls to stand down after allegations emerged in July that almost $700 million of payments made to a bank account in his name were linked to other 1MDB transactions. The claims over the fund and Mr Najib have spawned investigations in the US, Switzerland and Hong Kong.
Both Mr Najib and 1MDB deny wrongdoing. The prime minister says the money sent to his bank account was from an unnamed Middle Eastern donor.
Multiple domestic probes into the affair are also under way in Malaysia. Critics accuse the Malaysian authorities of trying to stifle these by removing investigators from their posts and slapping travel bans on critics in politics and the media.