Federal Labor has taken new Social Services Minister Scott Morrison to task for flagging welfare cuts to fund delivery of the national disability insurance scheme.

Just hours after being sworn in in his new role, Mr Morrison sent tremors through the welfare and disability sector by suggesting the government might need to prune spending on other welfare to pay for the full rollout of the landmark scheme.

The minister went further on Wednesday, telling News Corp that to achieve sustainability of the welfare safety net – “of which the NDIS is the holy grail” – sustainability in other parts of the system was needed.

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That meant welfare reform to get “those who don’t have to be on the system, could be off the system, should be off the system”.

Opposition disability reform spokeswoman Jenny Macklin labelled the minister’s comments as a “disgusting and cynical attempt” to cover the next round of savage welfare cuts.

“Any claim by Mr Morrison that the NDIS isn’t fully funded is completely disingenuous,” she said, citing a 0.5 per increase in the Medicare levy and federal budget allocations out to 2020.

The government argues any allocations Labor made outside the four-year forward estimates are unfunded.

Labor has said the money would come from long-term savings.

Mr Morrison challenged the opposition to back government welfare reform measures to ensure the NDIS could be delivered in full.

“Everyone supports the NDIS, but making it work is the hard part.”