A number of consumer groups have warned the DWP a "too broad" review of the 2012 reforms would compromise the "hard-won consensus" on auto-enrolment.
The group - including members of the Financial Services Consumer Panel, Citizens Advice, Trades Union Congress, Which? and AgeUK - has written to DWP ministers ahead of tomorrow's expected announcement on the future of NEST and auto-enrolment.
Their letter said: "We think that it would be a mistake to extend the review in a way that reopens the consensus reached about how best to implement the main recommendations of the Pensions Commission."
The group said it had "strong confidence" in PADA and very much welcomed Lord Freud's strong support for auto-enrolment in the recent House of Lords debate (PP Online June 17).
They highlighted the fact consensus on NEST was only secured through much consultation and a great deal of give and take between the various parties involved.
It said: "This is why we think that reopening these issues now could be destabilising. Any changes would require further parliamentary scrutiny and derail industry and employer plans. This would threaten the timetable which has already been delayed to wide disappointment.
"This would of course not just hit those who would save through NEST, but also the many other staff who would be auto-enrolled into other schemes, whether trust-based occupational schemes or commercial contractual group personal pensions."
It added: "Reopening these issues now - before there is any evidence of how employees and employers respond to the plans in practice - could result in the break-up of the wide coalition of support for 2012 and make it much less likely that the reforms attract the millions of new savers that we all want to see."
The group also called for a formal review and the establishment of a permanent, independent Pensions Policy Commission to be brought forward.
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