The Pensions Regulator (TPR) is "playing catch-up" with automatic enrolment regulations brought in last year, the Daily Telegraph reports.
Experts warned both the Department for Work and Pensions (DWP) and TPR are understood to be "very concerned" about bosses selecting inappropriate plans for their staff in the rush to offer workplace pensions under auto-enrolment.
The warning comes after last week's consultation from the regulator on suitable defined contribution pension set ups.
Hargreaves Lansdown head of pensions research Tom McPhail told the Telegraph the regulations had not been thought through properly and introducing standards three months after the laws came into effect suggested confusion.
"The DWP and TPR are playing catch up on the changes. They seem to have only belatedly realised that millions of people will be automatically enrolled into pension schemes which have very little standards. They are very concerned about employers selecting inappropriate plans," he added.
In a statement, TPR head of DC regulation Darran Burton said: "We expect all work-based pensions - both occupational DC trust-based and work-based personal pensions - to be able to display the principles and quality features, and we will carry out investigatory work to test for their presence across all types of schemes.
"We will expect providers of work-based personal pensions to be able to demonstrate in detail the effectiveness of the systems, controls, risk and compliance monitoring process.
"Compliance will give employers reassurance that they are choosing a suitable pension product, whether trust- or contract-based.
"Our code of practice and guidance relate to trust-based schemes, due to the scope of the regulator's legal powers.
"But we will agree joint working protocols with the FSA's successor bodies, and will share intelligence, to make sure that poor practice and breaches of law are dealt with."
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