Britain is facing a wave of threats to its food supplies - but self-sufficiency is not the answer, warns a government report.

The Defra study blames global terrorism, worldwide energy problems and conflicts abroad for a growing potential for disruption to availability of food.

But trying to combat this with a policy of greater UK food self-sufficiency would be "fundamentally misplaced and unbalanced".

The report pinpoints the power of globally sourcing supermarkets, a sharp fall in farm incomes, public health concerns about food safety, environmental fears and the risk of short-term interruptions to fuel supplies as worrying domestic factors. "Self-sufficiency fails to insulate a country against disruptions to its domestic supply chain and retail distribution. Domestic farm crises, such as a harvest failure or animal disease, will mean imports become critical to maintaining a stable food supply."

But NFU president Peter Kendall said: "The danger in assuming that importing more gives you greater flexibility is the assumption that when you want it, other people will let you have it.

"We should be looking for designated supplies of top-quality product as near to home as possible rather than importing it, say, from Thailand or Brazil."