The government has held firm in its refusal to bow to pressure to give almost six million children access to junior individual savings accounts (ISA).
Following the abolition of child trust funds (CTF) at the beginning of 2011, the government last year introduced the junior ISAs as the latest attempt to encourage saving from a young age.
However, children born between 2002 and 2011, have been denied access to the Junior ISAs, instead having to continue contributing to their CTF.
In a written question, Liberal Democrat MP Dan Rogerson asked the Treasury to consider allowing these children to be able to open a Junior ISA, perhaps by sealing their CTF until their 18th birthday.
However, financial secretary Mark Hoban echoed previous announcements that the government had no plans to do so.
"There are currently around 5.7 million Child Trust Fund accounts, with a total value of approximately £4.4bn," he said.
"The market continues to grow steadily and, so long as CTF account holders continue to exercise their right to switch accounts where appropriate, there will continue to be an impetus for providers to compete.
"We do not believe that the majority of the 5.7 million children with a Child Trust Fund would benefit from a change in rules at the present time."
Although he added the issue would continue to be kept under review, the latest refusal has frustrated those campaigning to get the rules changed.
Danny Cox, head of advice at Hargreaves Lansdown, said there was already evidence of some providers offering better rates on Junior ISAs than CTFs and insisted there would be almost zero cost to the Treasury to allow transfers.
"The problem here is that we are at the top of a slippery slope, where children with CTFs are already being disadvantaged in terms of choice and in some cases in the rate they are receiving.
"This situation will only get worse. As a test, simply compare the information available on Junior ISA and CTF providers websites, to see the difference in time, effort and money on promotion."
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