The aim of answering 80% of calls within five minutes would still see 16 million callers waiting longer than that to be answered by HM Revenue and Customs, its report said.

BBC: HMRC tax call handling 'must sharpen up'

Just before the report was released, customs officials in Malaysia announced that they had made a huge seizure of ivory.

BBC: Wildlife crime profound threat to nations, says report

He says South Korean Customs, which have bought the programme, report a 20% higher detection rate of illegal goods.

BBC: Risk profiling software tackles the terrorist threat