South Africa is building the world's most powerful radio astronomy telescope - the Square Kilometre Array (SKA) -- which is set to dwarf any other existing astronomy instrument.

The SKA project will suck in a broad investment expected to run to billions of US dollars, a bill South Africa expects its partners in the deal will have to pick up part of.

The bulk of the project will be built in South Africa's remote and arid south west in the Karoo region.

"Obviously South Africa is making a contribution, but the bulk of the money will be coming from member countries of the SKA consortium," Science and Technology Minister Derek Hanekom, told AFP.

SKA project director Bernie Fanaroff, told reporters late Monday ahead of Zuma's tour of the project site, that since Africa's economic and political powerhouse won the bid to host the SKA in May, negotiations have now turned to the "nitty-gritty" of the deal.

The two key agreements that parties to project are currently busy with are the funding and the hosting agreements, said Fanaroff.

"The funding agreement is always a big issue... all of the countries now are having to commit themselves to what part of the total cost of the SKA they will pay," said Fanaroff.

"Everyone at this stage is in a situation of financial stringency... So it is a fairly intensive negotiation," said Fanaroff.

But what is emerging clearly is that governments will make conditional commitments -- that they will part with their cash provided their own industries get contracts in the projects such as the supply of antennas, dishes or radio receivers, he added.

In all, the massive SKA radio telescope will link 3,000 antenna dishes. It will allow astronomers to see distant galaxies and to 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.

Aside from the co-hosts South Africa and Australia, other countries so far taking part in the SKA project are Britain, Canada, China, India, the Netherlands and Sweden. Germany is joining in weeks. Japan and South Korea have expressed interest.