The 16.5 billion dollar Carmichael coal mine project is one of the world's largest. : Melbourne: Adani on Monday said it has cancelled a 2.6 billion dollar contract with Australian mining services company Downer as part of a cost-cutting drive, a week after the Queensland government vetoed a concessional loan to the Indian giant for the controversy-hit Carmichael coal mine. The split comes after Downer was the target of a nationwide activist campaign pressuring them to quit the 16.5 billion dollar project in central Queensland, the ABC News reported.