NSW has threatened to derail federal government efforts at a meeting of treasurers on Friday to get the states to pay for more of the ballooning cost of the National Disability Insurance Scheme, as part of its push for urgent reform of the GST.

Premier Chris Minns has demanded federal Treasurer Jim Chalmers explain whether the Commonwealth Grants Commission decision to cut GST payments to NSW and send an extra $3.8 billion to Victoria was deliberate or accidental. Western Australia is set to reap an extra $6.2 billion through its sweetheart arrangements, angering east coast governments.