Ministers have been accused of jeopardising the livelihoods of thousands of farmers after it emerged that a new trade deal with Australia will permit huge increases in meat imports before any protective tariffs come into force. Concerns have also been raised about a lack of detail on animal welfare and environmental safeguards in the agreement, the UK’s first new trade accord with another country since Brexit. Boris Johnson, who finalised the outline of the agreement during talks at Downing Street with Australia’s prime minister, Scott Morrison, told reporters it would “benefit British farmers”. The British announcement of the deal said that farmers, many of whom are fearful about a potential flood of cheaper, lower-quality meat imports from huge Australian farms, would be protected by “a cap on tariff-free imports for 15 years using tariff rate quotas and other safeguards”. Downing Street declined to give any more details, saying they would come when the agreement in principle was published in the coming days. But in its own announcement about the deal, Australia’s trade ministry said tariffs for Australian farming imports into the UK would stop in as little as five years for dairy products. Beef and lamb tariffs will halt after 10 years, and after eight years for sugar. Labour said that even while the tariffs are in place Australian farmers will be allowed tariff-free quotas that are so high that the levies are effectively meaningless. For example, the beef tariff quota would start at 35,000 tonnes, rising every year during the tariff period. In 2019 the UK imported 1,766 tonnes of beef and veal from Australia. Tariffs on sheep meat products will start at 25,000 tonnes a year, and sugar at 80,000 tonnes. Emily Thornberry, the shadow international trade secretary, said the terms of the deal, and the fact it would set a likely precedent for other agreements, “will send thousands of farmers to the wall”. She said: “No other country in the world would accept such a terrible deal for its farming industry, and neither should we. Any Tory MP backing this deal today needs to have a hard look in the mirror, and ask how they would react if it had been proposed by Brussels instead.” The National Farmers’ Union (NFU) has called for more information about the tariff protections, and would seek details on how environmental and animal welfare standards would be protected. Australia uses much higher quantities of antibiotics in farming than Britain – 16 times on average for poultry – allowing farmers to crowd animals together, making meat cheaper to produce but with severe impacts on their welfare. The NFU’s president, Minette Batters, said: “We will need to know more about any provisions on animal welfare and the environment to ensure our high standards of production are not undermined by the terms of this deal.” Downing Street said the UK was “absolutely not compromising” its standards on food production and would not allow the import of hormone-treated beef. However, a spokesperson said he did not immediately know if there would be restrictions on antibiotic levels. Speaking alongside Morrison at No 10 on Tuesday, Johnson promised the deal would contain strict rules on animal welfare. “Here, we had to negotiate very hard and I want everybody to understand that this is a sensitive sector for both sides and we’ve got a deal that runs over 15 years and contains the strongest possible provisions for animal welfare.” “But I think it is a good deal and I think it’s one that will benefit British farmers and British consumers as well.” Greener UK, a coalition of 12 organisations including the National Trust, RSPB, Friends of the Earth and Greenpeace, said it would “look forward to seeing the safeguards that the UK government is building into the agreement”. MPs will get a chance to scrutinise the agreement once it is fully completed, expected to be near the end of the year. However, they will not get a vote on whether it comes into force. Both the tariff arrangements and welfare standards could cause disquiet among some Conservative MPs, as well as MPs in Scotland and Wales who represent farming communities. Government forecasts have said the deal will boost UK GDP by about 0.025% over 15 years. The outline arrangement also includes a reciprocal deal to allow easier travel and work for people aged under 35.