Council chiefs hope the call will increase sales and save British jobs in the cash-strapped industry.
Alison Clish-Green, chair of the LGA's rural commission said: `British farming has been at the heart of rural communities for centuries and the provider of quality and nutritious foods for the whole of the country.
`As this is a very difficult time for our farmers and the whole of British agriculture we must all pull together to help this troubled but vital industry.
The campaign, called Proud to Serve British, was launched by the National Farmers Union and is being backed by a directive from the Local Government Association this week to encourage the use of home grown produce and protect rural employment.
Survey evidence by local authorities highlights the importance of British agriculture which employs over 600,000 people (2.1% of the national workforce). This is larger than chemical industry and the motor manufacture industry.
In many rural areas of England and Wales agriculture accounts for over 10% of local employment and is even more vital to the lifeblood of the community.
Michael Jones, agriculture and rural affairs spokesman for Welsh councils added: `A huge number of jobs rely on the British food production industry and depend on its success.
`Local authority caterers as well as private outlets must try to ensure that wherever possible their customers are buying British.'
* The NFU launched its Proud to Serve British campaign in November 1998.