Pensions minister Steve Webb has called on the Association of British Insurers (ABI) to conduct its audit of high-charging legacy schemes to "far faster".
Speaking at a Westminster Employment Forum on the pension and annuities market, the minister also called on providers to "get pension schemes in order" to comply with proposed governance, quality and charging standards.
Webb said he welcomed the agreement from the ABI to look at schemes as a result of the Office of Fair Trading's (OFT) study in the defined contribution (DC) market.
However, he shared his view "speaking personally, not as a government minister" that the timeframe is not acceptable.
Webb said: "That has to happen far faster. I don't think we can sit and wait for a year while that work is carried out. They've got to get on with that, frankly."
The Liberal Democrat MP for Thornbury and Yate argued the proposed charge cap on qualifying DC auto-enrolment (AE) schemes is likely to have a wider impact on employers operating legacy schemes, as companies that cannot use existing products to enrol will be in a position to pressure providers or shop around for a better deal.
Webb said: "If we were to go ahead with a charge cap, it will be a real game changer."
Speaking about the timing of the charges consultation, which the Department for Work and Pensions (DWP) estimated could affect 90,000 AE schemes Webb admitted he would "rather have done it a year ago".
However, he said providers should be taking steps to adapt schemes to meet proposed quality standards and potential changes in charging.
Webb said: "We want good quality, good value for money schemes. Any provider that thinks the world past April will allow them to get away with anything other than that is kidding themselves.
"So come guys, you know roughly the likely direction of travel, get pension schemes in order and then you won't have a problem."
Change is vital to stop the "fragile, but treasured, reputation" of AE from being "tarnished", Webb added.
Webb also told delegates that the upcoming defined ambition paper will set out "enabling" options for both defined benefit and DC provision.
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