The key member of Jeremy Corbyn’s far Left front bench team made her ludicrous claim at a hustings organised by defence thinktank, the Royal United Services Institute (Rusi).
Ms Thornberry is best known for being sacked by Ed Miliband for her disparaging Tweet showing a house white van and an England flag during a byelection.
Shadow foreign secretary Emily Thornberry insisted Australia food products 'will go off'
Asked about the UK's future trade with major Commonwealth countries post-Brexit, Ms Thornberry said: "Things like our food industry, you can't export it to Australia – it will go off."
She appeared to be unaware that, accoring to the Food and Drink Federation, Britain exported exported £337.7 million worth of food & drink to Australia in 2016, up 12.4 per cent on the previous year.
Focusing further on the food industry, Ms Thornberry also claimed that British food would go off if Britain leaves the EU customs union.
Emily also claimed British food would go off if Britain leaves the EU customs union
Things like our food industry, you can't export it to Australia – it will go off.
Emily Thornberry, Shadow foreign secretary
Labour want the UK to stay in the customs union even though it would stop the UK from having its own trade deals.
She said: "It needs to be able to move smoothly across to Europe without there being points of origin checks, without us having Dover as a massive great lorry park whilst everything is checked through and so forth.
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"So I am very concerned, I'm very concerned about the practical effects of us leaving the single market but also about us leaving the customs union."
Emily was accused of being 'out of touch with reality' by Conservative candidate Neil Parish
Ms Thornberry, asked to clarify her remarks about the difficulties of trading with Australia, said after the hustings: "You could hardly sell breaded chicken breasts, you know.
Asked about her comments in light of New Zealand lamb being sold in the UK, Ms Thornberry said: "I appreciate that. But that's why I mean processed food, which is that much more complicated and you get ingredients from all over.”
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Jeremy Corbyn during a visit to Hackney Marshes Football Pitches, to highlight Labour's manifesto commitment to ensure 5% of the Premier League's television rights income is diverted to the grassroots game, during a General Election campaign
Neil Parish, Conservative candidate for Tiverton and Honiton and former chairman of the Commons Environment, Food and Rural Affairs select committee, said: “Yet again, Emily Thornberry is completely out of touch with reality. Australia is already our 12th biggest export market for food and drink and demand is growing fast – because our great British food makes it Down Under in perfect condition.
“These comments would be funny but it is no laughing matter that Jeremy Corbyn and Emily Thornberry could be negotiating Brexit just 11 days after polling day.
“If they don’t think we can export food around the world, they would make an absolute meal of the Brexit negotiations – and we would all pay the price.”