Mike Penning says NI Assembly must pass welfare reforms
It would be "absolutely ludicrous" if the assembly did not proceed with plans to reform the welfare state, Northern Ireland Office Minister Mike Penning has said.
MLAs are debating new legislation already passed in England and Wales.
It is designed to deliver the biggest shake-up in benefits for decades.
Under the changes six benefits, including housing benefit, would be brought together in a single, monthly Universal Credit payment.
The bill would also replace Disability Living Allowance (DLA) with a personal independence payment.
It would mean claimants being independently assessed every three years, instead of assessing themselves, as happens at the moment.
Sinn Fein wants to have the bill deferred to allow more negotiation with the government in Westminster, but other parties, including the DUP, say it must go through or NI risks losing millions of pounds in Treasury funding.
The SDLP have called for the bill to be delayed for 30 days in order to hold a special committee to consider the equality implications of the measure under Section 75 of the 1998 Northern Ireland Act.
The party's leader Alasdair McDonnell said that if their proposal is not accepted, they are prepared to table a petition of concern, which would subject the welfare reforms to a cross community veto.
Speaking at the Conservative Party conference in Birmingham, Mr Penning said the proposals "must not be deferred".
He said doing so would affect spending in Northern Ireland.
Mr Penning said MLAs should back the changes and dismissed suggestions that Northern Ireland should be a special case.
He said there were "lots of special cases around the country" and the assembly should "take the deal".
The minister said the objectives of the changes were to "get people off benefits and into work".
His comments were backed by the Enterprise Minister Arlene Foster who was also in Birmingham attending a fringe event focusing on the Northern Ireland economy.
The Fermanagh DUP MLA said was "totally irresponsible to hold up this bill".
Mark Devenport, BBC News Northern Ireland political editor
Stormont is used to rows between the parties in its power-sharing executive.
This disagreement between the DUP and Sinn Fein is serious, as there could be real financial consequences for benefit recipients if the principle of parity between NI and the rest of the UK is broken.
That said, there's a lot of brinkmanship on display.
Sinn Fein haven't used their power, under Stormont's cross-community voting system, to kill the bill.
DUP ministers warn lives could be lost if Stormont loses tens of millions of pounds - an argument they don't apply when talking about the cuts which would accompany, for example, any devolution of Corporation Tax.
The most likely outcome is that Northern Ireland gets flexibility in the way benefits are paid, but Westminster insists all parts of the UK remain equal when it comes to the financial level of welfare payments.
She said the place to make changes to the legislation was in committee stage.
Ms Foster claimed that if the changes were delayed there would be a knock-on effect.
"To stop the bill now will have repercussions for jobs, the block grant and the social fund," she cautioned.
She also suggested that up 1,500 jobs could be at risk.
The Sinn Fein MP Pat Doherty, who appeared on the same panel as Ms Foster in Birmingham, supported his party's stance on welfare reform.
"In its present format [the bill] is entirely unacceptable, so we have asked for real negotiations," he said.
The West Tyrone MP said Sinn Fein had taken this stance so the issue could be "resolved in a thorough way".
The new bill will affect tens of thousands of households in NI.
Sinn Fein has claimed the changes amount to Tory cuts. However, the Stormont Executive has decided to press on with the legislation rather than break with the UK-wide benefits system.
Social Development Minister Nelson McCausland is due to meet Welfare Reform Minister Lord Freud next week and negotiations are taking place about Northern Ireland's specific needs.
"We are well on the way to getting the flexibility we need in Northern Ireland," he said.
"There are elements in the bill that are unpalatable, but we are working and negotiating with government to get the flexibilities we need.
"But this legislation needs to be through by 31 March. There is no more slippage time left. It would be irresponsible if people were to attempt it."
Northern Ireland's largest public sector trade union is among those opposed to the legislation.
The Northern Ireland Public Sector Alliance (Nipsa) has claimed that working families and those looking for work would be worse off if the bill was passed.
Speaking last week, Prime Minister David Cameron defended the legislation.
He said his government was "tackling the welfare dependency that has harmed too many parts of our country, including Northern Ireland, for too long".