Government plans to extend care for the elderly have come under attack from some of Labour's own peers.
A former member of the Royal Commission on Long-Term Care, Lord Lipsey, said the £670 million plans to guarantee free care to the 280,000 most needy elderly and disabled people in their own homes amounted to "a demolition job on the national budget".
The Personal Care at Home Bill was a flagship of the Queen's Speech, designed to allay growing concern that pensioners are being forced to spend all their savings and sell property in order to fund care.
It was presented by the Prime Minister as a step towards his long-term ambition of establishing a National Care Service to match the National Health Service.
But Lord Lipsey told The Times Mr Brown's announcement was like "an admiral firing an Exocet into his own warship.
"I'm not looking forward to the night of the next general election but, if the result goes as I expect, one of the consolations will be that one of the most irresponsible acts to be put forward by a prime minister in the recent history of this country will be swept away with his government," said the Labour peer.
Meanwhile, former health minister Lord Warner told The Times: "There has been no proper impact assessment, and no data to show how this would work. There is a big question mark as to whether there is even actually a Bill ready."
Challenged over Lord Lipsey's comments, Cabinet minister Ben Bradshaw told BBC2's Newsnight: "It's not a 'demolition job'. It's a very, very small part of the National Health Service budget of £120 billion."
The Bill, outlined in the Queen's Speech, would guarantee free personal care at home for up to 280,000 elderly and disabled people with the highest needs - although 166,000 do already receive free care. A further 130,000 who need home care will also benefit for the first time from other measures, including adaptations to their homes - such as the installation of electronic pill dispensers.
Officials estimate that about 400,000 people will benefit from the measures in the Bill, which will cost £670 million a year to implement.
