A spokesman for 1MDB did not respond to requests for comment.
Bankers say 1MDB is pushing ahead with the sale despite an anti-corruption taskforce looking into allegations of graft and financial mismanagement at the fund, though caution the investigation will slow the process.
Malaysian police raided 1MDB's office in July following a report in the Wall Street Journal that said investigators looking into the fund found nearly $700 million had been put in to Prime Minister Najib Razak's bank accounts, citing documents from the investigation. Reuters has not verified the report.
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On Monday, Malaysia's anti-corruption commission said the funds deposited in Najib's accounts were from a donation, not from 1MDB, without elaborating on who the donor was.
Najib, who chairs 1MDB's advisory board, has denied taking any money for personal gain.
On Saturday, he said Qatar and China have expressed an interest in 1MDB assets, which include property projects as well as its energy portfolio, without specifying which ones.
Air of caution
1MDB has 14 power assets parked under Edra.
It is the largest independent power producer in Bangladesh and Egypt and the second biggest in Malaysia after Malakoff. It also holds assets in the United Arab Emirates and Pakistan through joint venture alliances.
One Southeast Asia-based banker who is familiar with the process and held talks with a bidder last week said buyers want the assets to be ring fenced so they are not affected by the political controversy.
"You are likely to see very low ball bids because it's not clear if this sale will go ahead or it is just an attempt to gauge interest from buyers," the banker said.
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Suitors have been given the option to pick selected assets or take the whole energy portfolio, though 1MDB would prefer it to be sold in one piece, according to bankers.
Interested parties include Middle Eastern power firm ACWA Power Qatar Investment Authority, Malaysian power firms Tenaga Nasional and YTL Power International.
1MDB has hired Maybank to manage the sale process, according to sources.
Maybank, ACWA Power, Qatar Investment Authority and Tenaga declined to comment on the story.
YTL Power did not respond to Reuters requests for comment.
Malaysia caps foreign investment in its power generation sector at 49 percent, which limits overseas buyers' ability to buy the entire business give its Malaysian assets.
Reuters reported in June that 1MDB was planning to scrap its planned $3 billion IPO of its power unit due to weak markets.