Prime Minister Andy Burnham is considering a 10 per cent levy on all estates after death to help fund an overhaul of social care.
The controversial proposal could replace inheritance tax and raise money towards a new National Care Service, which is estimated to cost up to £18.7billion a year.
Downing Street refused to rule out the policy on Monday when asked whether the Prime Minister still supported it.
Mr Burnham’s official spokesman said: “I’m just not going to get ahead of his update on this issue, which will come later in the week.”
He added: “He’s also been clear about the consequences of not doing it, which is that the NHS would collapse under the weight of having to care for people not really needed in the NHS system.”
Unlike the current inheritance tax system, a flat 10 per cent charge could apply to every estate, potentially requiring millions more families to pay tax when someone dies.
Mr Burnham first proposed abolishing inheritance tax and replacing it with a 10 per cent levy on all estates in 2009, when he was health secretary under Gordon Brown.
The plan was dropped after the Conservatives branded it a “death tax”, a description that proved politically damaging.
However, Mr Burnham has continued to raise the idea of using inherited wealth to pay for social care.
During the Makerfield by-election campaign in June, he told The Guardian that he would “look at all of the kind of implications” surrounding inheritance tax and care funding.
At a New Statesman conference two years earlier, he argued that inheritance tax should be changed so that people with greater wealth and more valuable assets contributed more towards the cost of care.
The Prime Minister is expected to provide an update on his plans later this week.
In his first major interview since entering Downing Street, he warned that the NHS could collapse unless the social care system was urgently reformed.
Speaking to the BBC’s Laura Kuenssberg, Mr Burnham said: “If we don’t do it, the NHS will collapse under the weight of trying to care for people who’ve really not needed to end up in the NHS system.”
He promised to use “whatever political capital I have” to secure meaningful change and said he would not want to leave office without delivering “substantial” social care reform.
