People taking retirement income through pension freedoms are at risk of huge bills from HMRC amid the confusion.
New rules affecting people who have started drawing money from savings were supposed to be introduced in April.
But the snap election delayed implementation of the accompanying legislation.
Under the proposed changes anyone taking taxable income from their pension would have the amount that can be saved into schemes slashed to just £4,000 a year.
It would mean the so-called Money Purchase Annual Allowance (MPAA) is cut by around 90 per cent from £10,000.
And anyone drawing their pension, but still wanting to save – for instance if they are also working – would incur a tax bill if they breached the new £4,000 annual limit.
Under the rule changes, savers who have taken their 25 per cent tax-free lump sum and has not drawn taxable income can still save up to £40,000 a year.
The Government should now consider pushing the rules back until 2018, say experts.
Tom Selby, senior analyst at AJ Bell, said: “While clearly Brexit is the dominant issue as the minority Conservative Government formulates its focus ahead of the Queen’s Speech, there is some serious unfinished business on pensions policy.
“More than two months after a cut in the Money Purchase Annual Allowance from £10,000 to £4,000 was supposed to have been introduced, we still don’t have the accompanying legislation.
“It would seem grossly unfair for HMRC to hit people who have accessed their pension flexibly from age 55 and subsequently paid in less than £10,000 with a tax penalty given the lack of clarity surrounding the policy.
“A sensible, pragmatic short-term solution would be to push back the cut until April next year at the earliest.”