A major miner says it is committed to a uranium project in WA, despite being knocked back by the state government. 

The WA Environment Minister has rejected an application from Canadian firm Cameco to extend approval for a uranium mine near Wiluna. 

Traditional owners and conservationists say the rejection is a relief, but the company says it is still determined to bring the project forward. 

Cameco spent US$430 million acquiring the Yeelirrie uranium deposit in 2012, giving it access to one of the largest uranium deposits in the country. 

The mine was approved by former federal environment minister Melissa Price without key protections that had been strongly and repeatedly recommended by the government's own experts.

The project's approval expired due to a failure to commence work earlier this year, and WA Environment Minister Reece Whitby has now denied the firm's application to have the approval extended.

Cameco’s application for a similar project at Kintyre in the Pilbara has been knocked back too. 

The company says uranium could provide an opportunity for cleaner energy, if the WA Government is willing to accept it.