Future contracts for Eskom's coal-fired Kusile power station have been put on hold, the electricity parastatal said on Thursday.

"Eskom has been proceeding with all placed contracts at Kusile ? however the unplaced contracts will remain so," spokesperson Andrew Etzinger told Sapa.

Contracts would be put on hold for around two months until the parastatal had received clarity on its proposal for tariff increases from the National Energy Regulator.

"Unless we have revenue certainty we can't place the contracts."

Construction at Kusile had not come to a halt as the work underway stemmed from contracts already placed.

"It's complete speculation to say whether or not the delays at Kusile will continue beyond the outcome of the tariff increase application to Nersa," Etzinger said.

Kusile power station, situated at Emalahleni in Mpumalanga, had been expected to satisfy 10 percent of the country's electricity demand.

The power station would reportedly cost around R120-billion to complete. Eskom has stated previously that the first unit of Kusile was expected to be completed by 2013 and would deliver 4800 megawatts.