LONDON (Reuters) - The British meat industry warned on Monday of looming border chaos as post-Brexit customs checks between Britain and the European Union (EU) halt some cross-border meat flows even with volumes sharply reduced. In an attempt to ease into the new customs checks, British meat companies have cut trade volumes with the EU and Northern Ireland to about 20% for the first two weeks of January, the British Meat Processors Association (BMPA) said. Even so, there have been “catastrophic delays”, said the group. It warned of worse to come as meat firms, together with a flood of other industries, are due to start ramping up exports from this week onwards. “The current paper-based customs and certifications system is a relic. It was never designed to cope with (an) integrated, just-in-time supply chain,” said Nick Allen, head of the BMPA. Under a deal reached last month, British trade with the EU remains free of tariffs and quotas on goods, but exporters, especially fresh produce sellers, say their businesses are still threatened by delays caused by customs checks. The BMPA said meat exporters have had consignments returned undelivered and that European customers are already turning away from UK suppliers. Moreover, some of Britain’s largest hauliers have ceased taking ‘grouped loads’ or consignments of mixed products, the BMPA said. About 40% of British meat trade with the EU is sent in this manner.