There is an ominous rumbling coming from somewhere to the south of my home, which looks out over the English Channel. It could be taken for the first stirrings of a major volcanic eruption but the worrying fact is that it is actually a sign of something potentially far more catastrophic: the imminent collapse of the eurozone.

The brinkmanship that has been played out in Greece in the last few days is not going to reassure anyone about the future of a single currency. But what, you are probably asking, has this got to do with farming? Quite a lot. Because while the euro has remained strong, the pound has been relatively weak. And that's a situation which has suited British livestock farmers very well indeed.

We have witnessed a torrent of exports to the continent, a trade which has been a real life-saver for a sector which has been severely battered by problems ranging from disease to costly new regulations to rising fuel and energy costs.

Even the sheep farmers have stopped bleating. The diversion of New Zealand meat to Far East and Asian markets coupled with the decision by many French producers to exit the sector has led to a huge continental trade in lambs – and a significant strengthening of domestic prices as a consequence.

All very good news. But a situation which will pertain only as long as the pound is relatively weak against the euro. If a Greek default, or some other seismic event, triggers a collapse in the euro's value, however, that rosy situation could come to an abrupt end.

And what worries me is that nowhere do I see anyone working on a Plan B: what to do if British exports suddenly become expensive. Nowhere do I hear talk of any contingency planning taking place for the eventuality where overnight British beef and lamb become luxury items for millions of continental consumers.

At the Oxford Farming Conference Farming Minister Jim Paice quite rightly identified a vacuum in the farming leadership in this country and called for a new organisation to be set up to fill it.

And Jim Paice must make sure his new organisation is dynamic, forward-looking and capable of taking and sticking to tough decisions. To that end its members must be hand-picked. We don't want any of the tired old donkeys from the NFU – an organisation which has become little more than an arm of government and has no experience of operating in the commercial sector.

We do need an entirely new crew of hard-nosed business experts with knowledge of farming economics but equally a degree of experience outside farming. We need a carefully hand-picked team of doers and go-getters, quick to assess situations and identify threats and respond to them rapidly.

We need an organisation which acts on the best available information with the best intentions for the best interests of farmers. And we need it quickly.

British farmers have faced significant challenges over the last few decades and will, it is inevitable, face many more in the years ahead. But there are few more pressing issues than the one making my windows rattle.

And few more worrying prospects than that of losing a major and very valuable market as a result of the Greeks being unable to pay their bills.