Rohan Sivajoti, who established Postcard Planning, has called for an end to tinkering “for a prolonged period of time”.
He accused the Government of “constant meddling” which he claimed had undermined savers’ confidence in pensions.
His comments come after national media reports today, which suggested David Cameron is urging George Osborne to “play it safe” on pension tax relief reform in next month’s Budget.
Changes to pensions tax relief are widely anticipated, following a Treasury consultation last summer, with a flat rate forecast to be on the cards.
A Pensions Isa has also been mooted, based on Mr Osborne’s comments at the July Budget and the Treasury review of the current pensions taxation system.
Mr Sivajoti, who recently became advisory services director at new robo-advice firm eVestor, said: “Rather than this latest plan to make further amendments to pensions rules, what we need now is a ban on pensions legislation changes for a prolonged period of time.
“It is vital that the public have confidence that the money they save for their retirement today will be treated in the same way when they retire, and the only thing all this constant meddling with pensions achieves is to undermine that confidence.
“It is no small wonder so many would-be investors have turned to assets like property rather than investing in their pensions when the goal posts are constantly being moved.
“The Government needs to realise this. It has a role to encourage and facilitate pension saving, but it will only happen if the process is straightforward.
“As it stands, many have become disillusioned with pensions simply because there is a lack of trust in the system. The public rightly questions, having locked their money away for many years, whether they will be able to access it again when they retire, and how it will be taxed?”
He added: “The Government must tackle this head-on by sticking to the current policies rather than once again making changes just to score political points.”