As Treasurer Jim Chalmers pushes for the biggest overhaul of the Reserve Bank of Australia in three decades, investors – both in Australia and overseas – will be watching closely as the Greens shape up to be his most difficult challenge.

Chalmers must decide whether to negotiate with the unpredictable Greens to shake up the RBA board structure and appoint new interest rate setters, after shadow treasurer Angus Taylor this week yanked his previous in-principle support for a dual board operation.