Theresa May wants a 'long-term' health funding plan in order to coincide with the 70th anniversary of the NHS this year.
The Prime Minister has hinted she is backing Health and Social Care Secretary Jeremy Hunt's call for a 10-year NHS spending deal as she warned of a need to get away from 'annual top ups' of hospital budgets.
Mrs May, appearing before the House of Commons Liaison Committee, described NHS funding as a 'critical priority' after highlighting 'serious cost and demand pressures' on the health service.
The Prime Minister suggested the Government 'cannot afford to wait until next Easter' - and a planned spending review for all Whitehall departments - for an answer to NHS spending.
'We need to, I think, get away from this annual approach we see to the NHS budget,' Mrs May told the group of MPs, made up of the chairs of all Commons committees.
'Recognise that for the NHS to plan and manage effectively we need to get away from those annual top ups of the budget that we see and we do need to have a sustainable long-term plan.
'And that, I think, should build on the work of the five-year forward view, but look beyond it and a plan which allows the NHS to realise greater productivity, to realise efficiency gains.
'This is a critical priority for me, so this year and in advance of next year's spending review, I do want to come forward with a long-term plan.'
The Prime Minister told the committee she wants plans for the NHS to be decided 'in conjunction with leaders of the NHS, with clinicians and health experts' and that the Government would back it with a 'multi-year funding settlement' to ensure 'the NHS can cope with the rising demand'.
'I would suggest that we can't afford to wait until next Easter,' she added.
'I think in this, the 70th anniversary year of the NHS's foundation we need an answer on this.'
Reacting to the Prime Minister's comments, NHS England chief executive Simon Stevens said: 'The Prime Minister's announcement of a funded long-term plan for the NHS this year is very welcome, timely and significant.
'The NHS celebrates seven decades of service this July, at a time of great pressure on frontline staff and great promise for improved care.
'So now is absolutely the right time to recommit to all that's best about our NHS, while also accelerating and capitalising on the huge promise of medical advance for the decade ahead.
'Charting a multi-year path for modern efficient and sensibly funded health and social care could mean huge gains for cancer patients, mental health services and support for frail older people, as well as the several million nurses, doctors and other care staff who devote their lives to looking after us.'
Labour's shadow health secretary Jon Ashworth described Mrs May's comments as 'warm words', but said voters should 'wait and see what the Prime Minister actually comes out with in a few weeks or a few months' time'.
He told Sky News: 'Theresa May has been a leading member of this Government for eight years, and after eight years the NHS is in absolute crisis.
'We've got waiting lists close to four million, we've got people, often elderly people, languishing on trolleys in overcrowded hospitals.
'We've been calling for a long-term funding plan for the NHS for some time. If we were in government now, we'd be putting an extra £5bn into the NHS.'
Setting out his wish for a 10-year funding settlement, he said: 'Given that it takes seven years to train a doctor and three years to train a nurse, you need to have something that gives you the ability to look ahead.'
The Prime Minister's announcement will be seen as a big political win within Cabinet for Mr Hunt, who Mrs May reportedly tried and failed to move from his health brief during her reshuffle earlier this year.