* Australian pension funds in joint approach for 50.4 pct stake
* Chinese, HK bids were rejected on national security concerns
* Majority stake had been expected to fetch over $7.9 bln (Recasts throughout)
By Byron Kaye
SYDNEY, Sept 23 (Reuters) - Australia's top two pension funds have made a joint indicative offer to buy a majority stake in the country's biggest electricity network, a month after bids from Chinese and Hong Kong interests were rejected on security grounds.
IFM Investors, which invests on behalf of about 30 Australian superannuation funds, and AustralianSuper made an unsolicited bid to buy a 50.4 percent stake in Ausgrid, the New South Wales state government said in a statement on Friday.
The government did not disclose the indicative offer price or other details of the proposal. IFM and AustralianSuper confirmed in a statement they had made a proposal.
The stake in the so-called "poles and wires" network was widely expected to fetch more than the A$10.3 billion ($7.9 billion) it got for a previous energy grid, an Australian privatisation record.
Last month, the state received final bids from government-owned State Grid Corp of China STGRD.UL and Hong Kong-listed Cheung Kong Infrastructure Holdings Ltd 1038.HK but the federal treasurer intervened to block the sale, citing unspecified national security concerns. led to a rebuke from the Chinese government which called the move protectionist and warned that it "seriously impacts the willingness of Chinese companies to invest in Australia". ($1 = 1.3103 Australian dollars)