The Chancellor has come under fire for failing to rule out measures ahead of the Budget.
Rumours that the tax-free lump sum would be cut prompted some savers to withdraw cash early. Wealth planners said knee-jerk reactions to speculation will have damaged pensioners’ retirement plans.
The Institute for Fiscal Studies (IFS) accused Ms Reeves of allowing speculation to circulate.
Paul Johnson, director of the IFS, said Ms Reeves had allowed “damaging” rumours to circulate “for so long”.
He added: “If there was never any intention to change the income tax treatment of pensions, then she should have said so.”
Ms Reeves is expected to unveil sweeping plans to reform Britain’s pension fund industry in her maiden Mansion House speech next week in a bid to boost investment in UK assets.
She is understood to favour Canadian-style pension reform, which would involve merging Britain’s local authority pension schemes.
Canada’s main public sector pension scheme collectively manages $2 trillion (£1.1 trillion) in assets for workers employed by the state. The UK’s Local Government Pension Scheme, by contrast, is divided into 86 individual funds worth a collective £360bn.
The Chancellor told reporters during a trip to North America that the size of Canadian pension schemes means they can invest in “far more productive assets like infrastructure than ours do”.
The Government was approached for comment.
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