Drug cartels are using large denomination euro notes to launder profits in Britain, prompting a joint operation between US federal agencies and British police, The Times has learnt.

In one case before the US courts, the authorities want to confiscate $11 million (£6 million) worth of the currency in suspected cocaine profits. The money, mostly in €500 and €200 notes, was about to be transported on British Airways flights from Miami to London. Traces of cocaine have been found on the notes, which were to be converted into dollars by the Knightsbridge company TTT MoneyCorp, according to the US Government.

A senior US police source said that federal agents had held talks with officers from British police forces to discuss the use of euros by drug money launderers. Detectives believe that more than $1 billion (£492 million) worth of euros is being smuggled into Europe by drug gangs every year.

Detective Chief Inspector Bob Wishart, from City of London Police, said: “There is an established method of laundering that is exploiting loopholes in financial legislation across two continents and it will take time to break it down.”

In papers put before the Federal Court in Miami last month, prosecutors outlined how large amounts of euros were set to be transported on a British Airways Flight 208 to Heathrow from Miami, handed over to TTT MoneyCorp and then transferred to a US dollar account held by Miami company Intertransfers.

There is no implication that British Airways or TTT MoneyCorp or Intertransfers knew or should have known the source of the cash appeared to be the profits of Colombian drug gangs.

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