New Zealand's Commerce Commission has announced plans to launch legal action against CBA's ASB, Westpac and ANZ in March next year over how they sold fixed interest-rate swaps contracts to farmers.In an echo of the swaps mis-selling cases in the UK - which are likely to cost the UK's four largest banks billions in redress settlements - the Commerce Commission said there was sufficient evidence to indicate the three New Zealand banks may have breached clauses of the Fair Trading Act relating to misleading or deceptive conduct."We have advised the banks of our views that swaps were misrepresented to rural customers," said commission chair Mark Berry. "I expect to have more talks with the banks about these views, and about the different facts that might apply to each of them, over the coming months," he said.The commission said interest-rate swaps contracts were typically provided to large corporate and institutional customers, but from 2005 were offered by various banks to rural customers throughout New Zealand. The commission began its inquiries in August last year, after a delegation of farmers protested that their interest costs had spiked to over 15 per cent, from five per cent, after the imposition of break fees and other costs in the wake of the global financial crisis. The commission said it was still investigating other financial institutions.An advocate for the farmers, Janette Walker, has told that hundreds of farmers bought NZ$6 billion of the swaps products before 2008, believing they would protect them against big interest rate rises, but were instead stung with big break fees and risk premiums when the GFC struck. She said she now expected the banks to settle in case-by-case deals with the farmers, which would be similar to the settlements reached in the UK.ANZ said its National Bank arm, which has since merged with ANZ, had sold the swaps contracts to farmers before the GFC, when interest rates were low. It said it was working with the commission. Westpac also said it was cooperating with the commission, but declined to make further comment, except to say that any proceedings bought against Westpac would be vigorously defended. ASB also said it was cooperating and declined to make further comment.