The Lifetime Isa looks like an "assault" on pensions, according to James Hay Partnership's strategic account manager.
Due to be launched in April 2017, the Lifetime Isa is designed for the under forties to make contributions and receive a 25 per cent bonus towards either their first home or their retirement.
Nick Sleep said the product paints a "confusing picture" as it looks like it is replacing pensions but does not receive the same form of benefits as current pensions.
He highlighted the fact the Lifetime Isa is "attacking, or challenging" the auto-enrolment convention which has been very successful in making contributions towards retirement over the last three or four years.
Mr Sleep said: "It seems a very odd thing to do, to challenge something that's been so successful and confuse the picture for someone who needs to be saving for retirement."
This is not the first time the Lifetime Isa has been criticised for potentially derailing auto-enrolment.
In October this year, pension provider Zurich's director of operational taxes Iain Mills, warned the Lifetime Isa must not pave the way for regressive pension reforms.
He said at that time as the government presses ahead with legislation for the Lifetime Isa, any move to replace pensions with Workplace Isas could "profoundly damage" auto-enrolment, which has been successful in engaging millions of people to save into a pension for the first time.
ruth.gillbe@ft.com
