Pumpkins are harvested at David Bowman Pumpkins in Spalding, central England September 25, 2013.The company produces four million pumpkins annually on its 450 acre farm, supplying supermarkets in Britain and exporting to Europe. Reuters / Nigel Roddis LONDON — Britain's food industry has warned that labour shortages after Brexit could leave over a third of its businesses unviable.

In a survey of the "farm-to-fork" supply from the Food and Drink Federation, 36% of businesses said they would be unable to adapt if they did not have access to EU labour after Brexit.

A severe labour shortage is becoming a realistic outcome in a sector dominated by European workers.

Thirty percent of the UK food and drink manufacturing workforce are European migrants, and the Brexit vote already appears to be deterring EU workers from moving in Britain.

In June, a 20% shortfall in European labour was blamed on the EU referendum result appearing "xenophobic" and "racist."

An April report by the Commons Environment Food and Rural Affairs Committee said increased living standards in Eastern Europe and a weak pound were also making the UK a comparatively less attractive place for many European workers.

The federation called on the government to guarantee the rights of nationals from the European economic area, an area of Brexit negotiations which is yet to be resolved.

FDF

A government spokesperson said: "In June we published our offer to protect the rights of EU citizens in the UK, confirming no-one living here lawfully will be asked to leave when we exit the EU and they will have a grace period to regularise their status."

But the FDF also found:

31% of respondents said EU nationals had left since the referendum;

47% said EU nationals were considering leaving the UK.

FDF director general Ian Wright said: "It is only a matter of time before the uncertainty reported by businesses results in an irreversible exit of EU workers from these shores.

"Without our dedicated and valued workforce we would be unable to feed the nation."