The Reserve Bank of Australia will introduce a flexible lever to the next round of its quantitative easing program, according to market economists, but such a twist could come at a cost, particularly if the central bank does not specify the amount and timeframe of future bond purchases.

Both ANZ and Westpac have speculated on the structure of the central bank’s third bond-buying program, to be decided upon at its July meeting. They expect the Reserve Bank to avoid setting a fixed target and instead start at $5 billion of purchases a week with the option to scale up or down.