A report issued today by the business, enterprise and regulatory reform committee said closing profitable branches would inevitably disadvantage large numbers of people, while community interest demanded lone village shops should survive.
Many councils are looking to either subsidise postal services or provide them themselves, as they fear closures will worsen social exclusion.
Essex CC is expected to issue guidance this month on how councils can work with the Post Office to offer services.
The MPs sympathised with complaints from councils that the Post Office has been tardy in providing financial information on the viability of threatened branches.
Chair Peter Luff said: “Post Office Ltd is the subsidiary of a company owned by the government and it receives substantial taxpayer support, yet there is little transparency about its finances. This is simply unacceptable.”