The mining tax is shaping up to be one of the biggest issues of the federal election and it's a sore spot for Kevin Rudd.

Yeterday mining company Xstrata suspended two mining projects in Queensland. One was worth $586 million, the other $600 million, and they would have created an estimated 3000 jobs. 60 contractors were sacked yesterday by Xstrata.

QLD Premier Anna Blight stepped in, asking the PM to "put down the baseball bats, to stop the advertising and get on with solving it". Rudd refutes Xstrata's claims that the RSPT is to blame for the projects' suspension.