Tesco, Morrisons and Sainsbury's have all imposed restrictions on bulk purchases after production in Spain was hit by crop damage from flooding late last year followed by unusually cold weather last month.
The limited supply of lettuces follows a continuing shortage of courgettes in Britain. Supplies of broccoli and aubergines have also been limited.
The shortages add to the problems for U.K. supermarkets who are already facing inflationary pressures as a result of the weaker pound since Britons voted to leave the European Union last year.
Vegetable production in the EU is at 60 percent of the normal level due to bad weather affecting producers right across the Mediterranean, from Greece to Spain, the Spanish Federation of Associations of Producers and Exporters of Fruits, Vegetables, Flowers and Live Plants (FEPEX) said.
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