Minister asks US to honour extradition treaty

US senators will hear a personal plea from a Home Office minister this week to save the British Government from further humiliation by dropping their opposition to a US-UK extradition treaty.

Baroness Scotland of Asthal will fly to Washington on Thursday - the same day that the three British bankers are due to board a plane in the custody of US marshals to face trial on fraud charges under a treaty that the US Senate is refusing to ratify.

David Bermingham, Gary Mulgrew and Giles Darby, former executives of NatWest, have been accused in the US of defrauding the bank of £4m by advising it to sell part of Enron for less than its real value. The three men left NatWest, bought the Enron business, and sold it on, for a profit of £1.4m each. The trio have denied any criminal activity and have insisted that if there is a case against them, it should be tried in a British court, but their appeal was rejected in the High Court.

The case of the NatWest Three has caused an outcry in the UK, because it is seen as another example of Tony Blair giving in to US pressure and getting nothing in return. The Home Secretary, John Reid, has told Lady Scotland to plead with the Senators to drop their opposition .

A Downing Street spokesman said "discussions" were under way to try to ensure that the three men would be treated in the same way as US citizens when they make an application. They want to be allowed to return to Britain to prepare their defence, but there are fears that the court could treat them as foreign fugitives and jail them unless they can raise a $1m bond.

The extradition, without evidence being produced in any British court, was made possible by a treaty signed between the US and the UK in March 2003, the same month that Tony Blair joined George Bush in the war against Iraq. In December 2003, Lady Scotland assured a Lords committee: "We anticipate that the treaty will be put before the Senate early in the new year and approved shortly thereafter."

The Government's embarrassment could be increased today if the House of Lords votes for a Liberal Democrat amendment that would go back to the pre-2003 arrangement, compelling the US to produce evidence before British citizens can be extradited.

"The Government ...should never have agreed to abolish the need for evidence to be produced when the American government seeks extradition, while still leaving it necessary for evidence to be produced when extraditing the other way," the Liberal Democrat shadow Lord Chancellor, Lord Goodhart, said.