It comes after the Queen’s Speech failed to give detailed proposals for the new system.
MPs have warned they will be “extremely disappointed” if the PM fails to produce a plan to reform adult social care in England by the end of the year.
The warning follows this week’s Queen’s Speech which did not include detailed proposals for long-term reform.
The cross-party Commons health and social care committee said the lack of funding detail could undermine plans to integrate health and care services.
The government has been asked for a response.
MPs on the committee have been scrutinising the plans for integrated care systems in the forthcoming Health and Care Bill.
The new systems mean local NHS and social care teams work together more closely, helping to reduce bureaucracy and focusing services better around patients’ needs.
But they say it is an omission to fail to give full details about the reform.
Boris Johnson had originally promised to “fix” the system when he became prime minister in July 2019 and has said he will bring forward proposals “later in the year”.
The committee said the forthcoming Health and Care Bill should include a statutory requirement for the health secretary to publish a detailed 10-year plan within six months of the legislation receiving royal assent.
In the report, the MPs said: “The absence of a fully-funded plan for social care has the potential to destabilise integrated care systems and undermine their success.
“However, we note that the prime minister has committed the government to producing a 10-year plan later this year; and we would be extremely disappointed if detailed plans for this were not published before the end of the calendar year.”
It added that the problems faced by the care sector over the past two decades “will not be solved” without “secure, long-term funding”.
There is a fundamental question being asked by MPs in this report. Can you really improve the way health and care systems work together for the people who need them, if one of those services is on its knees?
The problems for social care run deep. It has an underpaid, undervalued workforce leading to staff shortages.
Fewer people get council support now than a decade ago, even though an ageing population means more people are asking for help. And those who pay for their own care are charged extra to subsidise a system which has been underfunded for years.
The prime minister said nearly two years ago that he had a clear plan to “fix the crisis in social care once and for all”. In the Queen’s Speech on Tuesday, just nine words were used to repeat the promise of reform, but again, no detail or timetable.
This influential group of MPs is warning that without a vision for the future of care, plans for the future of the NHS are also being put in jeopardy.
Committee chairman and former health secretary Jeremy Hunt said if the issues were addressed, then the government had “an opportunity to deliver a post-pandemic watershed 1948 moment for the health and care system, matching the significance of the year the NHS was founded”.
He added that if they were not addressed, it would be “a wasted opportunity to deliver the truly integrated care required by an aging population”.
In 2019, 1.9 million people made requests for social care – including both older people and working age adults with disabilities, according to the King’s Fund.
Its chief executive Richard Murray said the reforms set out in the white paper could give the NHS “greater flexibility to deliver joined-up care” but said they would only go so far, however.
“The government has yet to say how it will tackle staff shortages, redress deep-seated health inequalities, or bring forward long-overdue reform of the social care sector,” he added.