South African President Jacob Zuma on Tuesday gave his political backing to negotiations with foreign partners to help fund the construction of the world's next generation radio telescope.

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 $2.5 billion, 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.

After touring the site, Zuma told reporters his government was fully behind the project.

"We have supported this fully because we understood that South Africa is at the cutting edge of science in the world," he said.

Science and Technology Minister Derek Hanekom told AFP that the "bulk of the money will be coming from member countries of the SKA consortium."

Canada, India, the Netherlands and Sweden are among those taking part in the project, China and Germany are expect to fully enter the fold soon and Japan and South Korea have expressed interest.

SKA project director Bernie Fanaroff said there was an expectation that telescope hosts South Africa and Australia -- and Britain which houses the project headquarters, should pay more.

But so far the US has kept an uncomfortable distance.

Fanaroff said funding talks have always been a "big issue."

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

Tuesday was Zuma's first visit to the site since Africa's economic and political powerhouse won the bid to host the SKA in May.

"The awarding of this project to South Africa is a major step in solidifying science and technology not only in South Africa, but in the African continent as well as across the globe," he told a residents and school children of this sleepy town of around 6,000 people.

"It will propel our continent to the forefront of radio astronomy.

"We are there, we are at the door of finding life in other planets, ... I think we are now at the cutting edge of that research, we are leaders of it," said Zuma.

Outgoing science minister Naledi Pandor told the Carnavon residents to let the world down by giving all their best to ensure the project succeeded.

But as she spoke crippling strikes continued in the mining and transport sectors elsewhere in the country.

There are fears the rolling labour unrest could put a damper on the foreign investment into the SKA project but Hanekom told AFP the multi-billion dollar scheme was unlikely to be hit.

Such industrial actions were common in open democracies "but obviously we want to manage that much better," he said.

"It's a normal phenomenon in open and free democracies in the world, so it actually places us among the developed nations of the world, rather than among the dictatorships of the world."

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.