Slashing regulations for farmers will be the government’s key priority for the agriculture sector as Britain leaves the European Union, the environment secretary, Andrea Leadsom, has promised.

Speaking at the Oxford Farming Conference, Leadsom announced one specific plan would be to end the “three-crop rule”, a measure designed to promote biodiversity on larger farms. This prompted criticism from the Green party, who called the idea “environmental irresponsibility”.

Leadsom, who has made few public pronouncements since taking the job in July, said too much time and money had been wasted on keeping up and complying with EU red tape.

She said: “Over the past six years we’ve done everything we can to reduce this burden, but I’m quite sure everyone here can still think of at least one piece of EU regulation you won’t miss.

“Now, as we prepare to leave the EU, I will be looking at scrapping the rules that hold us back and focusing instead on what works best for the UK.”

The three-crop rule, which was agreed by EU agriculture ministers in 2013, decrees that some larger farms must grow a variety of crops.

The measure is designed to mitigate the impact modern mass farming can have on the environment and local biodiversity and is unpopular with many British farmers.

However, the Greens condemned the plan. Molly Scott Cato, a Green MEP who sits on the European parliament’s agricultural committee, said the government seemed “determined to dive headlong into encouraging damaging monocultures”.

Leadsom’s announcement came on the day that a committee of MPs warned that departure from the EU could spell big problems for wildlife and habitats.

The Commons environmental audit committee said there could still be issues even if EU regulations were incorporated into UK law, and warned farmers could face a cut in income after Brexit.

The government has guaranteed farmers will receive the same level of financial support until at least 2020. Leadsom said her department’s rural development programme would provide an additional £120m to support rural growth.

However, the bulk of her address focused on what Leadsom argued was a “big potential win for farmers” through a promised bonfire of EU regulations on agriculture.

“No more 6ft EU billboards littering the landscape,” she said. “No more existential debates to determine what counts as a bush, a hedge, or a tree. And no more ridiculous, bureaucratic three-crop rule.

“By cutting the red tape that comes out of Brussels, we will free our farmers to grow more, sell more and export more great British food whilst upholding our high standards for plant and animal health and welfare.”

The Country Land and Business Association (CLA) welcomed her speech. Ross Murray, the CLA’s president, said: “Brexit presents the best possible prospect to design new rules to govern the way we farm and manage land. We can achieve increased productivity and improved environmental outcomes though a new world-leading food, farming and environmental policy and we are committed to working with ministers to deliver on this once-in-a-generation opportunity.”

This article was written by Peter Walker Political correspondent, for theguardian.com on Wednesday 4th January 2017 11.57 Europe/London

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