BIG business, MPs and human rights campaigners united to condemn the Government’s new extradition policy with the US after three former NatWest bankers lost a landmark High Court battle to avoid being extradited to America on fraud charges.

Lord Justice Laws ruled that it would be “unduly simplistic” to treat the case as a purely English affair and that he could not refuse the request to extradite David Bermingham, Giles Darby and Gary Mulgrew for trial.

American prosecutors allege that the trio conspired with executives at Enron, the collapsed energy trader, to defraud their then employer — the NatWest subsidiary Greenwich Natwest — of $7.3 million through the cut-price sale of its stake in a Cayman Islands firm to Enron.

The judgment drew widespread fury from critics, who insisted it was a British case and should be tried in this country.

The CBI said that the ruling set a worrying precedent under which UK executives could be extradited without proof that there was a case to answer.

Under the 2003 Extradition Act, designed to deal with suspected terrorists, America is able to demand a Briton’s extradition without having to provide any evidence. However, Britain has to prove its case in a US court to extradite US citizens to the UK.

Vince Cable, the Liberal Democrats’ Treasury spokesman, described the Extradition Act yesterday as “appalling” and “dreadfully one sided”.

Shami Chakrabarti, director of Liberty, the human rights group, said Britain was “trading away the freedoms” of its citizens. “If we are wrong that this is a violation of fundamental rights, why will the US Government not allow similar traffic for its own citizens in the other direction?”