Ministers are expected to announce plans imminently that will limit the sky-high bills pensioners in care homes face following a review by economist Andrew Dilnot.
The Government risks abandoning the most vulnerable pensioners if it introduces a cap on care cost contributions, a leading think tank has warned.
But the Centre for Social Justice (CSJ), which was founded by Work and Pensions Secretary Iain Duncan Smith, has claimed the move is low priority and fails to improve the lives of the poorest pensioners.
It has called for the money that would be needed to fund such a cap to instead be used to tackle the "serious systemic failings" of the social care system.
Christian Guy, managing director of the CSJ, said: "The current social care crisis cannot be leapfrogged. People delivering care services can think of much better ways to spend the £3.5 billion that is about to be invested in the Dilnot proposals.
"The Government should take a step back and seriously reconsider the purpose of only implementing the Dilnot proposals.
"The CSJ has spent years studying the social care system in the UK and the Dilnot plans set to be implemented will not improve the lives of our poorest pensioners who are already receiving sub-standard care. Surely helping the most disadvantaged must be the starting point for any reforms.
"The coalition's first priority should be to repair the current broken system and invest money in a way that will transform the lives of our most vulnerable pensioners. Once this is done and the situation dramatically improves, the Dilnot recommendations could be phased in so help can be extended to all."
The Dilnot review recommended setting a cap of between £25,000 and £50,000 to stop pensioners being forced to sell their homes to cover the costs of their care, although Department of Health analysis showed the Government has looked at a number of options, including a £75,000 and a £100,000 limit.
But the proposals fail to address a raft of problems, including neglect of the elderly and their poor treatment at understaffed and poorly regulated care homes, according to the CSJ.
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