Federal resources minister Matthew Canavan has accused Westpac of acting like "wimps" in the face of environmental campaigners and subtly encouraged Queenslanders to bank elsewhere, after Westpac indicated it would not fund Adani's Carmichael coal project.

The extraordinary attack came after Westpac effectively ruled out lending to the controversial Carmichael mine when it vowed not to lend to new mines in previously undeveloped coal basins or mines that produce coal with low energy content.