Labour is refusing National's challenge to provide estimates of how much an increase in the KiwiSaver saving rate would be needed to prevent a 1 per cent rise in interest rate rises through the official cash rate.
Labour finance spokesman David Parker said the call to provide such a figure was part of a "narrow little game"and he was not going to play it. However, associate finance spokesman Trevor Mallard posted some rough estimates on Twitter last week.
Finance Minister Bill English and Economic Minister Steven Joyce have condemned Labour's new monetary policy tool, known as variable savings rate (VSR), which would give the Reserve Bank governor an additional tool in controlling inflation as well as the ability to raise or lower interest rates.
Labour wants KiwiSaver made compulsory and the bank given the power to lift or lower employees' minimum savings rate within a range yet to be finalised as an additional tool to take heat out of the economy or to free up spending.
While it could cut workers' take-home pay by forcing them to save more, Labour argues the advantage would be going to the saver's KiwiSaver account, not in interest rate rises to overseas banks.