UK to experience shortages of some fresh foods for weeks or even months if a disorderly no-deal Brexit leaves perishable produce rotting in lorries at ports, Britain’s food and drink lobby warned on Wednesday.

Leaving the EU in October 31 on a non-orderly manner, will be problematic as so much fresh produce is imported and warehouses are stocked full ahead of Christmas, according to Britain’s grand retailers.

450,000 people are employed in the doing and food industry, and this will be the first major challenge since the horse meat scandal of 2013 and the mad cow disease outbreaks of the 1980s and 1990s.

According to the Food and Drink Federation’s Chief Operating Officer Tim Rycroft, no-deal Brexit could disrupt food supplies “for months.” “We’re not going to starve but there will be shortages of fresh food and some specialist ingredients. It’s going to be a little bit unpredictable,” Rycroft said.

“Given that food very often is perishable and has a short shelf life, we expect that there will be some selective shortages of food in the weeks and months following no-deal Brexit,” Rycroft added warning on possible price raises.

Ahead of the original Brexit deadline of March 29, supermarkets and retailers spent millions of pounds preparing for Brexit and working with suppliers to increase stocks of dried goods including pasta, bottled water and toilet paper. Today things seem uncertain, as after three years of Brexit negotiations, it is unclear whether the UK will strike a last-minute exit deal or delay to an acrimonious divorce that would knot the sinews of trade. “A lot of money will be spent,” Rycroft said, referring to how the industry prepared for two previous Brexit deadlines in March and April.

UK premier Boris Johnson has repeatedly warned the EU that if no new withdrawal agreement is gradated, he will lead the country out of the bloc without a deal.

A no-deal Brexit looking ahead to 2019-2020 winter, when Britain inevitably becomes more dependent on imported food, a Halloween no-deal Brexit is potentially more disruptive. Around 60 percent of the UK’s food needs are imports in November, such as fresh fruit and vegetables, produces with a short shelf-life of only a few days, that cannot be stored for long, posing problems if long queues form at Calais.

Rycroft said they estimated that the cost of preparing for a no-deal exit, including reserving warehouse space, using alternative distributors and losing orders in congested ports, would cost the industry up to 100 million pounds a week. These numbers come from the UK food and drink industry, which accounts for 19% of the manufacturing sector by turnover and employs over 450,000 people in Britain across 7,000 businesses including Associated British Foods Plc , Nestle and PepsiCo .

“The UK will be leaving the EU on 31 October and our top priority is supporting consumers and businesses in their preparations for Brexit,” said a spokeswoman for the government.