URANIUM miner Energy Resources of Australia is pinning its chances of returning to profitability on a medium-term China-led surge in demand for the nuclear fuel.

But post-Fukushima uncertainty in Japan meant the uranium market -- in which spot prices had eased to $US50 a pound -- would remain challenging in the short term.

The outlook comments came as ERA, a 68 per cent listed subsidiary of Rio Tinto, posted a $59.86 million loss for the June half. The loss had been flagged in previous guidance.

The result was an improvement on the $121m loss in the previous corresponding period, when ERA's Ranger mine, in Kakadu National Park, was shut down for most of the period by heavy rainfall.

Open-cut mining at Ranger is expected to end by the end of the year, with ERA switching the operation to treating low-grade stockpiles, with jobs cuts expected. The long-term future of the operation depends on accessing the Ranger 3 Deeps resource, now the subject of a $57m pre-feasibility study and a $120m exploration effort

ERA is also out to improve its relationship with the traditional owners of the project area. It has said previously it will not develop the nearby Jabiluka deposit -- one of the world's biggest undeveloped uranium deposits -- without the consent of the traditional owners.

ERA's revenue from uranium fell to $148m, from $235.6m in the June half, due to lower sales volumes, lower prices and the higher US exchange rate.

The average price for its uranium was $US57.57 a pound, down from $US60.82 a pound.

The company said short-term uranium demand remained challenging because power utilities were well supplied and the situation in Japan remained uncertain.

Despite news of some restarts in Japan, the spot price for uranium remained stable at $US50 a pound, with little activity and low volatility.

The longer-term outlook, however, "remains encouraging for established producers".

"Demand in China continues to grow, with 26 reactors currently under construction," ERA said. "Despite some slower growth in the medium term as China transitions to an increased reliance on improved nuclear power generation technology, it is expected that the country will be one of the largest uranium consumers within the decade."

Low spot prices in the past year had led to some supply-side reductions.