An inquiry by the housing, communities and local government select committee into local government finance and the 2019 Spending Review concluded that "current uncertainty for local government and the lack of funding for services must be addressed as a matter of urgency".
The report said rising demands of social care, both for adults' and children's social care, are placing increasing strain on local government budgets.
"These services help some of the most vulnerable in society so must be properly funded," it said.
The report warned that the current four-year financial settlement for local councils, which has allowed them to plan ahead, is now coming to an end. A three-year Comprehensive Spending Review - which was due to be delivered in the autumn - will now be shelved until late 2020 due to issues surrounding the UK's exit of the European Union.
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Chancellor Sajid Javid said the one-year spending round, due next month, will ensure departments and devolved administrations have the financial certainty they need to deliver their plans on public services next year.
But the committee said the lack of clarity on funding for the coming years is an issue.
"The resulting uncertainty is causing problems for local government," the report states.
"Without clarity about funding in 2020 some local authorities will need to prepare for the worst, making decisions which may unnecessarily reduce spending and represent poor value for money in the longer term."
The MPs said if central government wants councils to continue providing the services it currently does it needs to provide local government with a "significant real-terms increase in its spending power".
To restore local government expenditure to the position it was - as a share of GDP in 2000/01 - would require an increase of around £4bn before taking into account the increased demands for services such as adult social care and children's services over the last 20 years.
A report by the committee published in May, which looked specifically at children's services funding, concluded that only increased central government funding in the next Spending Review, as well as systemic change, can help prevent the children's services "crisis" from deepening further.
Rachel Dickinson, president of the Association of Directors of Children's Services, said: "This report provides yet more evidence that there is not enough funding in the system to meet the level of need in our communities, what is missing is action from the Treasury.
"The messages in this report are nothing new, neither are our repeated pleas to government to invest in local authorities and their children's services.
"Since 2010 our funding has halved but need has not. Small, time-limited pots of funding aimed at single issues for some local authorities over others are not a replacement for sustainable funding for all, which would enable us to invest in a whole range of early help and preventative services that improve outcomes and life chances as well as reduce future demand.
"Ahead of the forthcoming Spending Round, we urge the Treasury to think of proper and sustainable funding for children's services, and schools, not as a burden but as an investment in this country's future. Our children deserve more than just the bare minimum levels of resourcing and support."