Asda, Sainsbury's and Lidl give cause for concern — but Waitrose, M&S, Tesco, Morrisons, Budgens and Aldi are all looking good.

Overall November's Porkwatch survey shows the supermarkets maintaining their support for British pork, ham and sausages. But they are slipping back on bacon, compared to the September survey.

When compared with the same time last year, the retailers are up on British bacon and ham but slightly down on British pork and sausages.

The Porkwatch survey measures British shelf facings rather than volume, but the two are closely linked.

Maintaining 100 percent British fresh pork are Aldi, Budgens, Co-op, M&S, Morrisons, Sainsbury's and Waitrose.

But Asda is down on British bacon, ham and sausages, Lidl is down on British pork, ham and sausages, and Sainsbury's is down on British bacon, ham and sausages.

Verdict? Overall a good performance by the retailers especially at a time of intense price rivalry and plentiful cheap continental supplies — but there are weak areas which need watching.