The NHS will be promised a £1.5 billion cash boost in the Autumn Statement to deal with winter pressures in 2015/16, Nick Clegg has signalled.
As top-level coalition negotiations continue over the contents of next week's package, the extra funding has been a prominent Liberal Democrat demand.
But the Deputy Prime Minister said he did "not anticipate a great political stand-off" over its inclusion in Chancellor George Osborne's package on December 2.
"I believe we should and I believe we will," he told reporters about putting aside money to cover costs beyond next year's general election.
There appeared to be cross-party support for the " compelling analysis" of the funding needs compiled by NHS chief executive Simon Stevens, he said, which concluded that another £8 billion a year will be needed by 2020 on top of efficiency savings.
The extra £1.5 billion was "broadly derived" from that analysis, he suggested, adding that the Government had to "walk the walk and not just talk the talk" when it came to health spending.
"I have come to the view that we need to now agree a step-change in the amount of financial support that we give to the NHS in the years to come," he said at his monthly Westminster press conference.
"I do not anticipate a great political stand-off about this."
Health Secretary Jeremy Hunt has already announced that £700 million more has been found to cover this winter.
"We should be saying that we are not only going to make financial commitments to the NHS now. We are also going to make sure that the NHS is handed over - whoever is in government after next May - in a way which allows all the millions of outstanding nurses, doctors and consultants to do so confident that they will have the backing necessary to deal with not only this winter's pressures but next winter's pressures as well," Mr Clegg said.
"That is very much something which is on the agenda in our discussions within Government as we prepare for the Autumn Statement."
Mr Clegg said he hoped the move would give reassurance to the hundreds of thousands of health workers, including midwives, nurses, radiographers, cleaners and psychiatric staff, staging their second strike in a month over pay rises.
"I hope the kind of vision that I am setting out today - a properly-funded NHS and a properly-supported mental health service within the NHS - will give them and everybody confidence that the NHS is going to be properly catered for in the years ahead," he said.
The Deputy Prime Minister also announced that he would chair a task force of senior Cabinet ministers to ensure mental health issues were being considered and "properly integrated" in policy-making across Whitehall.
He also said he was determined to tackle "u nfair discrimination" against mental health services by switching them away from block grant funding - that was too easy a target for "bean counters" seeking savings to the sort of per-patient model used for other health services.
Asked whether David Cameron accepted the need for an extra £1.5 billion for the NHS to cover winter 2015/16, the Prime Minister's official spokesman told a regular Westminster media briefing: "You've seen the Government put in additional money this year for winter pressures - £700 million.
"You've seen additional funding in previous years. And you have the Prime Minister's longstanding commitment to frontline services in the NHS.
"That isn't going to change. That's the approach to the NHS the Prime Minister is going to keep taking."
Shadow public health minister Luciana Berger said Mr Clegg's mental health task force was part of a "confusing picture" within government about how to respond to the "crisis".
She said: "This is simply trying to recreate the Cabinet sub-committee that Jeremy Hunt scrapped soon after becoming Health Secretary.
"Mental health services are falling further and further into crisis under this Government and rather than acting to reverse the damage they have done their response has been to set up yet another review.
"On their watch, mental health funding has been disproportionately cut, we have seen a drop of 3,300 mental health nurses, the loss of 1,500 beds, and vulnerable patients forced to travel hundreds of miles to get the help that they need.
"This latest review comes only a few months after the care minister launched another task force on children's mental health. We now need urgent action from the Government to clear up this confusing picture and get to grips with the crisis in mental health services."