An international consortium planning to build the world's most powerful radiotelescope is still debating whether South Africa or Australia should host the $2 billion project, an official said Friday.

Scientists hope the Square Kilometre Array, or SKA, will shed new light on fundamental questions about the universe, including how it began, why it is expanding and whether it contains life beyond our planet.

The SKA board of directors met Monday in Manchester, England, where the project is headquartered, to discuss the still-secret recommendation of the best host for the hundreds of antennas that will pick up faint signals from across the universe.

"We don't really know" when the final decision will come, Bernie Fanaroff, director of SKA Africa, told AFP.

The board on Monday agreed to pass the site recommendation to the members of the consortium, which is set to meet on April 3 in Amsterdam, it said in a statement on its website.

"It is not likely that this meeting will make a final decision on the site; rather it will be the start of a process of discussion and negotiation between the members," it said.

A decision had been expected on April 4.

If South Africa wins the bidding, engineers will connect antennas in the arid Karoo region by remote link to a network of dishes stretching across southern and eastern Africa and as far away as Ghana.

Australia's bid puts the core site at Mileura station, about 100 kilometres (60 miles) west of Meekathara in western Australia. Other antennas would be distributed across Australia and New Zealand.

The new instrument will be 50 to 100 times more sensitive than today's most powerful radio telescopes.