Britain's National Farmers Union wrote to Prime Minister Boris Johnson on Friday calling for import tariffs on eggs, some dairy products, horticultural products and grains if Britain leaves the European Union without a trade deal.
British agricultural exports to the EU are expected to face tariffs under a no-deal scenario, but in March the government under then Prime Minister Theresa May announced a plan to eliminate tariffs on many imports, including some dairy products and agricultural products, to avoid a so-called hard border with Ireland.
"There is no indication that such an arrangement will be reciprocated by the EU and there is nothing in practical terms to stop this trade becoming an open gateway for all EU goods entering the UK duty free," NFU president Minette Batters said in a statement.
Export tariffs on agricultural goods would most likely lead to a surplus of domestic products on the UK market, she said, while at the same time lower or no tariffs on imports would put further downward pressure on domestic producer prices.
The farming group also asked the government to review its plan not to impose tariffs on the land border with Ireland if it leaves the trading bloc without a deal on Oct. 31.
A no-deal Brexit would be a disaster for British farming and any exit from the EU must be smooth and orderly, she said.
"If we leave without a deal the sudden change in our trading relationship with the EU will have severe impacts on the UK food and farming sectors, not least due to the tariff treatment of both imports and exports," she said.
Batters said the government should revise its tariff regime to lessen the damage no-deal would inflict on UK farming.
"It is also important that government manages prices for the public in a no-deal scenario - these tariff arrangements will have little impact on retail food prices yet could have a massive impact on the viability of farm businesses," she said.