And the industry won many new friends, not least in IGD itself, which had initially been less than pleased at the prospect of disruption of its high-profile event.

IGD chief executive Joanne Denney-Finch said that she wished that rather being outside, Ladies in Pigs had been in the lobby of the Royal Lancaster Hotel, serving delegates British bacon butties as they arrived.

Speaker after speaker - and chairman Michael Buerk - made positive mention of the 70 pig producers outside in the driving rain, who were putting their message across in a measured but high-impact manner.

The demo message was that if the market is allowed to take its course, there will be unprecedented inflation in pork, bacon, ham and sausage prices in a year’s time, and shoppers will be the losers.

Joanne Denney-Finch came out to meet the demonstrators and was supportive when producer James Black explained the importance of supermarkets building and maintaining sustainable supply chains.

"The BPISG demonstration was more than 70 pig industry people holding up placards and handing out leaflets on a London pavement," said BPISG spokesman Ellen Furby.

"What we are doing is bringing home the reality of the crisis to retailers. We hope this will flavour their view of us, and our urgent need for a fair price, for several weeks to come.

"It has helped add some real-life drama to the NPA and BPEX 'British Pigs Are Worth it' campaign. We were on the pavement providing the modelling clay whilst Stewart Houston was inside at the IGD Congress attempting to make some working models from it."

NPA's Barney Kay, Ian Campbell and Ann Petersson were present at the request of BPISG and are convinced the demonstration was worthwhile.