The government must quadruple the number of customs agents in the UK to ensure businesses struggling with mountains of Brexit red tape do not “buckle” under the strain, Labour has said in a letter to Michael Gove. The shadow chancellor for the duchy of Lancaster, Rachel Reeves, put it to Gove that industry figures showing that only 12,000 customs agents have been trained fell far short of the 50,000 the government accepted last February would be necessary to cope with Brexit. “Can you please … inform me what the government is doing to address this shortfall as swiftly as possible, so that businesses don’t have to deal with even more disruption?” she wrote. Reeves’ letter comes as hauliers, freight forwarders and existing customs agents say businesses are struggling with the new trading regime. Customs agents are the private operators who are contracted to do the paperwork for businesses and are separate to the army of officials recruited by HMRC to check the documents are in order. Last February, Gove told the Commons he would stand by his pledge to recruit the estimated 50,000 agents needed within six months. But in December, Bloomberg reported (£) that the £84m fund to train the agents was running dry despite the need for them at the end of the Brexit transition period. “What steps are the government taking to address this, and how will it support businesses as they grapple with huge amounts of new red tape and disruption?” Reeves wrote. “It is in the interests of us all for British business to thrive under the new UK-EU trading relationship. As hauliers and the industries they support buckle under unprecedented red tape through no fault of their own, they need a plan of practical support from the government urgently.” In the past, the government has estimated 147,000 businesses who trade internationally have no prior experience of customs because they have only sold goods to EU states. Several businesses told the Guardian they have had to wait days for a response from HMRC to customs queries. Others have told how businesses went into Brexit with little clue as to how complicated the new customs declarations, regulatory and transit certification and VAT rules would be. Colin Jeffries, a freight forwarder, said it was “absolute carnage”, with customers not knowing what they needed to do to trade and EU hauliers rejecting UK deliveries because of new requirements for financial guarantees for lorry-loads of goods. A Conservative party source said: “Rachel Reeves is being misleading, because as she knows the government made no such promise. Labour under Sir Keir Starmer spent the last four years seeking to overturn the 2016 referendum result, and trying to block Brexit, opposing our plans to take back control of our borders and arguing we were spending too much money on preparations.”