Leighton Holdings subsidiary contractor Thiess will undertake the contract, which includes the provision of the necessary mining fleet, plant operations and onsite management team to deliver Western Desert's production requirements.

"We are delighted to award our mining services contract to a tier 1 contractor with an experienced management team and proven track record in order to manage and deliver our mining, load, haul and dump operations over the next three years," Western Desert managing director Norm Gardner said.

The contract begins today.

Thiess has been providing ground mobilisation and project support for Western Desert since November last year.

Thiess managing director Bruce Munro said he was delighted to be returning to the region.

"Our offering to Western Desert Resources is based on our ability to provide both safe and efficient operations to our client," he said.

"We are very pleased with the flexible relationship that's been developed and look forward to a successful and long-term partnership."

The contractor also emphasised a shared vision for providing opportunities to indigenous Australians in the region.

"We have a shared strategy with Western Desert Resources to offer indigenous Australians training and employment opportunities and this includes a partnership with Rusca Bros Mining, which has a well-established connection with local communities," Thiess Australian mining executive general manager Michael Wright said.

Western Desert officially opened Roper Bar last month at the Bing Bong port facility.

The project covers 1700sq.km and only 20% of the total area has been explored.

The deposit drilled out so far holds 600 million tonnes grading 40% iron, including 47Mt of direct shipping ore grading 57.3% iron.

The company said it believed more mineralisation would be found as further exploration was carried out and up to 2 billion tonnes of iron ore could be within the whole province.

Based on forecast annual production volumes and stable iron ore prices and exchange rates, Western Desert estimated that Roper Bar could deliver annual turnover of up to $450 million.

Shares in Western Desert were last trading 0.7% higher at 71.5c while Leighton shares were down 0.9% to $16.23.