It is hard to believe how much and how quickly events in Ukraine have changed the world. Policies fixed in stone, not least net zero to tackle climate change, have given way to a realisation that keeping the lights on, homes heated and food on the table is more important.

In terms of response, the UK has talked the talk, but over refugees and sanctions on Putin's oligarchs it is the EU that has, to date, walked the walk.

This was not how it was supposed to be after Brexit. It should have left the UK in a position to act decisively and speedily, free of the need to secure agreement with 27 sovereign member states. This is the biggest challenge to face the EU since the collapse of communism and the accession of countries escaping from Russian influence. It is also the first time the EU has faced a crisis on this scale without the steadying diplomatic influence of the UK. Until Brexit it was widely respected and admired across Europe.

Neither London or Brussels will admit the pursuit of net zero is faltering, but that will be clear from policy decisions. The EU and UK are vulnerable to any loss of Russian gas and fracking and North Sea oil and gas are back on the political agenda. There is even talk of reversing the decision to end all power generation from coal, although many of the dual facility plants have been dismantled.

There is also a growing realisation that food supplies are at risk. The organisation that represent EU grain traders, oil crushers and the feed industry have jointly warned there is no pain free alternative to the supplies that came to Europe from Ukraine.

It was a huge exporter of proteins and wheat, while Russia was a source of ammonium nitrate and phosphate for the fertiliser industry. Wheat exports from Ukraine to the EU last year topped 11 million tonnes out of the 60 million tonnes of grain it exported. The loss of these raw materials can only mean one thing – higher prices on top of already high prices. There will be no easing of the fertiliser problem.

But these issues go further, in that it is not only about price, but the availability of products to buy at any price. In a repeat of what happened with Covid vaccines, rich countries will have deep pockets and poor countries equally dependent on grain imports will not be in a position to compete.

This is bound to influence consumer perceptions about green issues. Food and energy are the keys to survival and as prices rocket and drive inflation, economic recovery from Covid will soon be snuffed out. Politicians know that and it leaves them with no option other than to back pedal on net zero. A vociferous lobby will complain that the gains they made are at risk, but politicians know the issues that are important to people. Those are current, and people will not accept being told they must make even greater sacrifices to deliver a green nirvana in twenty years time.

When it comes to agriculture this is being grasped in the EU. EU farm ministers, admittedly promoted by France holding the rotating EU presidency, are moving onto an emergency footing. They have accepted that 'food sovereignty' – the new term for food security – must not only move up the agenda but be implemented.

They have agreed to implement the new post-Covid food crisis programme to release funds to farmers facing problems because of the market situation and the rising cost of inputs. Beyond that they have agreed there is a case for relaxing environmental restrictions, not least leaving land fallow, to get more crops grown. They have concluded there will be no quick fix to the Ukrainian situation. There is even talk of crop production becoming compulsory.

Now is the time for the UK farming lobby to really hammer home the message that food security is on a par with energy security. The UK is no longer part of the EU and if the crunch comes it is no better placed than any other third country to rely on supplies from the EU.

Consumers must tell the government to forget pie in the sky green dreams and trade deals based around long supply chains and cheap southern hemisphere food. The Westminster government must end its plans to kill off agriculture's role as a food producer.