The Liberal Democrats have promised to keep the "triple lock" on state pensions but plan to scrap the winter fuel allowance for pensioners with incomes above £45,000.
People with incomes in the 40 per cent tax bracket would lose the allowance which can be worth up to £300 a year and is currrently paid to all pensioners.
Originally introduced by the coalition government in 2010, the triple lock promises to increase the state pension by the higher of inflation, average earnings, or 2.5 per cent.
Labour is also pledging to maintain the triple lock but the Conservatives have yet to confirm their policy.
Speaking to the BBC, former Business Secretary Sir Vince Cable said: "Liberal Democrats believe that an important test of a civilised society is the way in which it cares for the elderly.
"The guiding principle of the pensions system must be to ensure that none are left unable to meet their basic needs for survival and participation in society, and that everyone is treated with the respect and dignity they deserve."
Under the proposals, an estimated 600,000 pensioners with annual incomes above about £45,000 - 5 per cent of those under 80 and 2 per cent of over-80s - would lose the winter fuel payment, saving the Treasury around £105m.
The Liberal Democrats have also proposed a 1 per cent rise in income tax across all bands to raise £6bn to improve health and care provision.
The triple-lock has seen pensioner incomes rise faster than average since 2007.
Analysis by the Institute for Fiscal Studies showed pensioners had seen their incomes rise by 15 per cent since the recession while average income among the 22-30 year olds has only just recovered to 2007/08 levels.
The recent state pension review by John Cridland called for the triple lock to be scrapped, citing "unfairness", which drew support from recent former pensions minister, Ros Altmann.
Baroness Altmann has suggested removing the 2.5 per cent element of the policy, creating a "double lock".
stephanie.hawthorne@ft.com
