Ian Norris, the former Morgan Crucible chief, and other business executives already facing trial in America will not be saved by Government plans to scrap the controversial extradition regime.

Sources close to the process said the Government will amend the extradition rules in October but it is understood that implementation of the changes will probably be delayed by as much as a year in a move that will allow the US to complete extradition requests already in the pipeline. It is understood the Government's present thinking is to deny extradition requests from the US concerning alleged crimes committed primarily on UK soil.

America's case against both Norris and the NatWest Three is based on alleged wrong-doing that lost American investors money but which was carried out primarily - or, in the case of the NatWest Three, entirely - in Britain.

Under the proposed new regime neither Norris, who denies US charges of price-rigging, nor the NatWest Three could have been sent to the US.

It is understood that Government lawyers have spoken to top QCs about a draft amendment to the much-criticised 2003 Extradition Act, which was intended to allow fast-track extradition of terrorism suspects to the US in the wake of the September 11 attacks.

Instead the new regime was unexpectedly used by America to target suspected white-collar criminals, including the NatWest Three who were extradited last July for alleged fraud related to the collapse of Enron. The three men - David Bermingham, Giles Darby and Gary Mulgrew, who deny any wrong-doing, are awaiting trial in Texas.

Norris will probably go to the US in January unless the House of Lords backs his final appeal against extradition. His lawyer, White & Case partner Alistair Graham, said any move to delay the implementation of rule changes would unfairly hit an innocent man.

Other lawyers back this view. Mike Pullen of DLA Piper said: "If the Government sees the need for an amendment, why delay it for 12 months? People are going to suffer a major miscarriage of justice of the Government's own making."

The Confederation of British Industry (CBI), which has lobbied for changes to the extradition regime said it would welcome reform of the law, but said it would like to see the Government go further by forcing the US to provide more evidence that the people it is seeking to extradite have done something wrong.

Before the 2003 Act, the US had to show they had substantial evidence that the person they wanted to extradite had committed a crime or a prima facie case.

But America complained this meant the bar for them to get extraditions from Britain was set higher than for Britain to get extraditions from the US.

Since the 2003 Act, British courts have not heard arguments about the strength of evidence when considering extradition requests. Yet lawyers argue that British courts seeking to extradite US citizens still have to prove their case.

Rod Armitage, the CBI's head of company affairs, said: "Extradition is supposed to work on the basis of reciprocity. This doesn't address that point."

The CBI is also worried about the wide range of countries from whom Britain will consider extradition requests, some of which have much weaker human rights protections.

Countries to which the UK will extradite include Russia, which is refusing to hand over Andrei Lugovoi, the man suspected of -poisoning former KGB agent Alexander Litvinenko in London.