The Reserve Bank of New Zealand's governor, Graeme Wheeler, has rejected claims by the Green Party that he has a bias in favour of the country's Australian-owned banks. And he has defended statements saying the lenders' return on equity is still below pre-crisis levels.Yesterday, Wheeler released bank profitability figures that the RBNZ had earlier given to the Green Party. He then used them to support comments made before the New Zealand Parliament's finance and expenditure committee that bank profits were "about average or below" those of other developed nations.The Greens' co-leader, Russel Norman, accused Wheeler of misleading Parliament over the claim, which isn't directly addressed in the RBNZ statement."The governor was wrong to tell Parliament that our foreign-owned banks are only making average or below-average profit,'' Norman said."Our new governor's complacency about bank profitability is concerning. His job is to regulate our banks, not be their champion."Wheeler released charts showing New Zealand's banks' after-tax return on assets and equity between 2009 and 2001 was in the bottom half of OECD countries, excluding the euro area. Pre-tax returns show New Zealand lenders' returns in the top six for the period. The comparisons aren't clear-cut, with some countries' returns shown as before tax and others after tax."My response to the select committee represented my understanding of the information available at the time," Wheeler said in a statement. "Our analysis was completed after the hearing and we released to the Green Party in response to their request which followed the hearing."The November 7 select committee hearing on the central bank's financial stability report was Wheeler's first appearance before politicians.Wheeler rejected the Greens' claim that the central bank is biased towards the Australian lenders, saying the bank "takes seriously its mandate from Parliament to supervise the New Zealand banking system and does so without favour."The Australian lenders' profitability had recovered on a return-on-assets basis, but was still below pre-global financial crisis levels as a return on equity, Wheeler said."That's partly because these banks are building up capital as part of the tougher Basel III regulatory requirements," he said.