Infrastructure Australia has assessed the project, known as the Australia-Asia Powerlink scheme, as "investment-ready".
Sun Cable is developing large-scale dispatchable renewable energy in the Northern Territory that would provide zero emission electricity to Darwin and Singapore.
"Set to be the largest solar farm, largest battery and longest subsea electricity cable ever developed globally, the proposal would deliver lower electricity prices for the NT and develop a new renewable energy export industry for northern Australia," Infrastructure Australia said in a statement on Friday.
"Sun Cable is continuing to develop the project, including by securing environmental approvals, commercial agreements to underpin demand and final funding arrangements."
The precinct, in the Barkly region of the NT, will generate 17-20 gigawatts of solar energy.
In comparison, Australia's largest power station - Loy Yang A and B in Victoria -Â has a capacity of 3.6 GW, although the power generated per GW of capacity is higher for coal-fired energy than for solar PV.
An 800km overhead transmission line will carry power to near Darwin, and a 4200km subsea cable will take electricity from the NT capital to Singapore, providing up to 15 per cent of the city-state's energy needs.
Construction is indicated to start in 2024, with the Darwin offtake completed by 2026 and the Singapore link by 2029.